Precalculus: Graphical, Numerical, Algebraic Common Core 10th Edition
Precalculus: Graphical, Numerical, Algebraic Common Core 10th Edition
10th Edition
ISBN: 9780134673301
Author: Waits, Foley, Kennedy, Bock Demana
Publisher: PEARSON
bartleby

Concept explainers

bartleby

Videos

Expert Solution & Answer
Book Icon
Chapter P, Problem 7RE
Solution

Write the given number in scientific notation.

  3.6×109 miles

Given information:

The mean distance from Pluto to Sun is about 3,680,000,000 miles.

Formula used:

Scientific notation of a number is written in between 1 to 10 and multiplied by the power of 10.

Calculation:

In order to write the given number

3,680,000,000 miles

in scientific notation, write it as a number between 1 to 10 multiplied by the power of 10.

  3,680,000,000 miles=3.6×109 miles

Since there are 9 terms after the first term so the 9th power of 10 is taken.

Thus, the scientific notation of given number is:

  3,680,000,000 miles=3.6×109 miles

Chapter P Solutions

Precalculus: Graphical, Numerical, Algebraic Common Core 10th Edition

Ch. P.1 - Prob. 1ECh. P.1 - Prob. 2ECh. P.1 - Prob. 3ECh. P.1 - Prob. 4ECh. P.1 - Prob. 5ECh. P.1 - Prob. 6ECh. P.1 - Prob. 7ECh. P.1 - Prob. 8ECh. P.1 - Prob. 9ECh. P.1 - Prob. 10ECh. P.1 - Prob. 11ECh. P.1 - Prob. 12ECh. P.1 - Prob. 13ECh. P.1 - Prob. 14ECh. P.1 - Prob. 15ECh. P.1 - Prob. 16ECh. P.1 - Prob. 17ECh. P.1 - Prob. 18ECh. P.1 - Prob. 19ECh. P.1 - Prob. 20ECh. P.1 - Prob. 21ECh. P.1 - Prob. 22ECh. P.1 - Prob. 23ECh. P.1 - Prob. 24ECh. P.1 - Prob. 25ECh. P.1 - Prob. 26ECh. P.1 - Prob. 27ECh. P.1 - Prob. 28ECh. P.1 - Prob. 29ECh. P.1 - Prob. 30ECh. P.1 - Prob. 31ECh. P.1 - Prob. 32ECh. P.1 - Prob. 33ECh. P.1 - Prob. 34ECh. P.1 - Prob. 35ECh. P.1 - Prob. 36ECh. P.1 - Prob. 37ECh. P.1 - Prob. 38ECh. P.1 - Prob. 39ECh. P.1 - Prob. 40ECh. P.1 - Prob. 41ECh. P.1 - Prob. 42ECh. P.1 - Prob. 43ECh. P.1 - Prob. 44ECh. P.1 - Prob. 45ECh. P.1 - Prob. 46ECh. P.1 - Prob. 47ECh. P.1 - In Exercises 4752, simplify the expression. Assume...Ch. P.1 - In Exercises 4752, simplify the expression. Assume...Ch. P.1 - Prob. 50ECh. P.1 - Prob. 51ECh. P.1 - Prob. 52ECh. P.1 - Prob. 53ECh. P.1 - Prob. 54ECh. P.1 - Prob. 55ECh. P.1 - Prob. 56ECh. P.1 - Prob. 57ECh. P.1 - Prob. 58ECh. P.1 - Prob. 59ECh. P.1 - Prob. 60ECh. P.1 - Prob. 61ECh. P.1 - Prob. 62ECh. P.1 - Prob. 63ECh. P.1 - In Exercises 63 and 64, use scientific notation to...Ch. P.1 - Prob. 65ECh. P.1 - Prob. 66ECh. P.1 - Prob. 67ECh. P.1 - Prob. 68ECh. P.1 - Prob. 69ECh. P.1 - Prob. 70ECh. P.1 - Prob. 71ECh. P.1 - Prob. 72ECh. P.1 - Prob. 73ECh. P.1 - Prob. 74ECh. P.1 - Prob. 75ECh. P.1 - Prob. 76ECh. P.2 - Prob. 1QRCh. P.2 - Prob. 2QRCh. P.2 - Prob. 3QRCh. P.2 - Prob. 4QRCh. P.2 - Prob. 5QRCh. P.2 - Prob. 6QRCh. P.2 - Prob. 7QRCh. P.2 - Prob. 8QRCh. P.2 - Prob. 9QRCh. P.2 - Prob. 10QRCh. P.2 - Prob. 1ECh. P.2 - Prob. 2ECh. P.2 - Prob. 3ECh. P.2 - Prob. 4ECh. P.2 - Prob. 5ECh. P.2 - Prob. 6ECh. P.2 - Prob. 7ECh. P.2 - Prob. 8ECh. P.2 - Prob. 9ECh. P.2 - Prob. 10ECh. P.2 - Prob. 11ECh. P.2 - Prob. 12ECh. P.2 - Prob. 13ECh. P.2 - Prob. 14ECh. P.2 - Prob. 15ECh. P.2 - Prob. 16ECh. P.2 - Prob. 17ECh. P.2 - Prob. 18ECh. P.2 - Prob. 19ECh. P.2 - Prob. 20ECh. P.2 - Prob. 21ECh. P.2 - Prob. 22ECh. P.2 - Prob. 23ECh. P.2 - Prob. 24ECh. P.2 - Prob. 25ECh. P.2 - Prob. 26ECh. P.2 - Prob. 27ECh. P.2 - Prob. 28ECh. P.2 - Prob. 29ECh. P.2 - Prob. 30ECh. P.2 - Prob. 31ECh. P.2 - Prob. 32ECh. P.2 - Prob. 33ECh. P.2 - Prob. 34ECh. P.2 - Prob. 35ECh. P.2 - Prob. 36ECh. P.2 - Prob. 37ECh. P.2 - Prob. 38ECh. P.2 - Prob. 39ECh. P.2 - Prob. 40ECh. P.2 - Prob. 41ECh. P.2 - Prob. 42ECh. P.2 - Prob. 43ECh. P.2 - Prob. 44ECh. P.2 - Prob. 45ECh. P.2 - Prob. 46ECh. P.2 - Prob. 47ECh. P.2 - Prob. 48ECh. P.2 - Prob. 49ECh. P.2 - Prob. 50ECh. P.2 - Prob. 51ECh. P.2 - Prob. 52ECh. P.2 - Prob. 53ECh. P.2 - Prob. 54ECh. P.2 - Prob. 55ECh. P.2 - Prob. 56ECh. P.2 - Prob. 57ECh. P.2 - Prob. 58ECh. P.2 - Prob. 59ECh. P.2 - Prob. 60ECh. P.2 - Prob. 61ECh. P.2 - Prob. 62ECh. P.2 - Prob. 63ECh. P.2 - Prob. 64ECh. P.2 - Prob. 65ECh. P.2 - Prob. 66ECh. P.2 - Prob. 67ECh. P.2 - Prob. 68ECh. P.2 - Prob. 69ECh. P.2 - Prob. 70ECh. P.3 - Prob. 1QRCh. P.3 - Prob. 2QRCh. P.3 - Prob. 3QRCh. P.3 - Prob. 4QRCh. P.3 - Prob. 5QRCh. P.3 - Prob. 6QRCh. P.3 - Prob. 7QRCh. P.3 - Prob. 8QRCh. P.3 - Prob. 9QRCh. P.3 - Prob. 10QRCh. P.3 - Prob. 1ECh. P.3 - Prob. 2ECh. P.3 - Prob. 3ECh. P.3 - Prob. 4ECh. P.3 - Prob. 5ECh. P.3 - Prob. 6ECh. P.3 - Prob. 7ECh. P.3 - Prob. 8ECh. P.3 - Prob. 9ECh. P.3 - Prob. 10ECh. P.3 - Prob. 11ECh. P.3 - Prob. 12ECh. P.3 - Prob. 13ECh. P.3 - Prob. 14ECh. P.3 - Prob. 15ECh. P.3 - Prob. 16ECh. P.3 - Prob. 17ECh. P.3 - Prob. 18ECh. P.3 - Prob. 19ECh. P.3 - Prob. 20ECh. P.3 - Prob. 21ECh. P.3 - Prob. 22ECh. P.3 - Prob. 23ECh. P.3 - Prob. 24ECh. P.3 - Prob. 25ECh. P.3 - Prob. 26ECh. P.3 - Prob. 27ECh. P.3 - Prob. 28ECh. P.3 - Prob. 29ECh. P.3 - Prob. 30ECh. P.3 - Prob. 31ECh. P.3 - Prob. 32ECh. P.3 - Prob. 33ECh. P.3 - Prob. 34ECh. P.3 - Prob. 35ECh. P.3 - Prob. 36ECh. P.3 - Prob. 37ECh. P.3 - Prob. 38ECh. P.3 - Prob. 39ECh. P.3 - Prob. 40ECh. P.3 - Prob. 41ECh. P.3 - Prob. 42ECh. P.3 - Prob. 43ECh. P.3 - Prob. 44ECh. P.3 - Prob. 45ECh. P.3 - Prob. 46ECh. P.3 - Prob. 47ECh. P.3 - Prob. 48ECh. P.3 - Prob. 49ECh. P.3 - Prob. 50ECh. P.3 - Prob. 51ECh. P.3 - Prob. 52ECh. P.3 - Prob. 53ECh. P.3 - Prob. 54ECh. P.3 - Prob. 55ECh. P.3 - Prob. 56ECh. P.3 - Prob. 57ECh. P.3 - Prob. 58ECh. P.3 - Prob. 59ECh. P.3 - Prob. 60ECh. P.3 - Prob. 61ECh. P.3 - Prob. 62ECh. P.3 - Prob. 63ECh. P.3 - Prob. 64ECh. P.3 - Prob. 65ECh. P.3 - Prob. 66ECh. P.3 - Prob. 67ECh. P.3 - Prob. 68ECh. P.3 - Prob. 69ECh. P.3 - Prob. 70ECh. P.3 - Prob. 71ECh. P.3 - Prob. 72ECh. P.3 - Prob. 73ECh. P.4 - Prob. 1QRCh. P.4 - Prob. 2QRCh. P.4 - Prob. 3QRCh. P.4 - Prob. 4QRCh. P.4 - Prob. 5QRCh. P.4 - Prob. 6QRCh. P.4 - Prob. 7QRCh. P.4 - Prob. 8QRCh. P.4 - Prob. 9QRCh. P.4 - Prob. 10QRCh. P.4 - Prob. 1ECh. P.4 - Prob. 2ECh. P.4 - Prob. 3ECh. P.4 - Prob. 4ECh. P.4 - Prob. 5ECh. P.4 - Prob. 6ECh. P.4 - Prob. 7ECh. P.4 - Prob. 8ECh. P.4 - Prob. 9ECh. P.4 - Prob. 10ECh. P.4 - Prob. 11ECh. P.4 - Prob. 12ECh. P.4 - Prob. 13ECh. P.4 - Prob. 14ECh. P.4 - Prob. 15ECh. P.4 - Prob. 16ECh. P.4 - Prob. 17ECh. P.4 - Prob. 18ECh. P.4 - Prob. 19ECh. P.4 - Prob. 20ECh. P.4 - Prob. 21ECh. P.4 - Prob. 22ECh. P.4 - Prob. 23ECh. P.4 - Prob. 24ECh. P.4 - Prob. 25ECh. P.4 - Prob. 26ECh. P.4 - Prob. 27ECh. P.4 - Prob. 28ECh. P.4 - Prob. 29ECh. P.4 - Prob. 30ECh. P.4 - Prob. 31ECh. P.4 - Prob. 32ECh. P.4 - Prob. 33ECh. P.4 - Prob. 34ECh. P.4 - Prob. 35ECh. P.4 - Prob. 36ECh. P.4 - Prob. 37ECh. P.4 - Prob. 38ECh. P.4 - Prob. 39ECh. P.4 - Prob. 40ECh. P.4 - Prob. 41ECh. P.4 - Prob. 42ECh. P.4 - Prob. 43ECh. P.4 - Prob. 44ECh. P.4 - Prob. 45ECh. P.4 - Prob. 46ECh. P.4 - Prob. 47ECh. P.4 - Prob. 48ECh. P.4 - Prob. 49ECh. P.4 - Prob. 50ECh. P.4 - Prob. 51ECh. P.4 - Prob. 52ECh. P.4 - Prob. 53ECh. P.4 - Prob. 54ECh. P.4 - Prob. 55ECh. P.4 - Prob. 56ECh. P.4 - Prob. 57ECh. P.4 - Prob. 58ECh. P.4 - Prob. 59ECh. P.4 - Prob. 60ECh. P.4 - Prob. 61ECh. P.4 - Prob. 62ECh. P.4 - Prob. 63ECh. P.4 - Prob. 64ECh. P.4 - Prob. 65ECh. P.4 - Prob. 66ECh. P.4 - Prob. 67ECh. P.4 - Prob. 68ECh. P.4 - Prob. 69ECh. P.4 - Prob. 70ECh. P.4 - Prob. 71ECh. P.5 - Prob. 1QRCh. P.5 - Prob. 2QRCh. P.5 - Prob. 3QRCh. P.5 - Prob. 4QRCh. P.5 - Prob. 5QRCh. P.5 - Prob. 6QRCh. P.5 - Prob. 7QRCh. P.5 - Prob. 8QRCh. P.5 - Prob. 9QRCh. P.5 - Prob. 10QRCh. P.5 - Prob. 1ECh. P.5 - Prob. 2ECh. P.5 - Prob. 3ECh. P.5 - Prob. 4ECh. P.5 - Prob. 5ECh. P.5 - Prob. 6ECh. P.5 - Prob. 7ECh. P.5 - Prob. 8ECh. P.5 - Prob. 9ECh. P.5 - Prob. 10ECh. P.5 - Prob. 11ECh. P.5 - Prob. 12ECh. P.5 - Prob. 13ECh. P.5 - Prob. 14ECh. P.5 - Prob. 15ECh. P.5 - Prob. 16ECh. P.5 - Prob. 17ECh. P.5 - Prob. 18ECh. P.5 - Prob. 19ECh. P.5 - Prob. 20ECh. P.5 - Prob. 21ECh. P.5 - Prob. 22ECh. P.5 - Prob. 23ECh. P.5 - Prob. 24ECh. P.5 - Prob. 25ECh. P.5 - Prob. 26ECh. P.5 - Prob. 27ECh. P.5 - Prob. 28ECh. P.5 - Prob. 29ECh. P.5 - Prob. 30ECh. P.5 - Prob. 31ECh. P.5 - Prob. 32ECh. P.5 - Prob. 33ECh. P.5 - Prob. 34ECh. P.5 - Prob. 35ECh. P.5 - Prob. 36ECh. P.5 - Prob. 37ECh. P.5 - Prob. 38ECh. P.5 - Prob. 39ECh. P.5 - Prob. 40ECh. P.5 - Prob. 41ECh. P.5 - Prob. 42ECh. P.5 - Prob. 43ECh. P.5 - Prob. 44ECh. P.5 - Prob. 45ECh. P.5 - Prob. 46ECh. P.5 - Prob. 47ECh. P.5 - Prob. 48ECh. P.5 - Prob. 49ECh. P.5 - Prob. 50ECh. P.5 - Prob. 51ECh. P.5 - Prob. 52ECh. P.5 - Prob. 53ECh. P.5 - Prob. 54ECh. P.5 - Prob. 55ECh. P.5 - Prob. 56ECh. P.5 - Prob. 57ECh. P.5 - Prob. 58ECh. P.5 - Prob. 59ECh. P.5 - Prob. 60ECh. P.5 - Prob. 61ECh. P.5 - Prob. 62ECh. P.5 - Prob. 63ECh. P.5 - Prob. 64ECh. P.5 - Prob. 65ECh. P.5 - Prob. 66ECh. P.5 - Prob. 67ECh. P.5 - Prob. 68ECh. P.5 - Prob. 69ECh. P.5 - Prob. 70ECh. P.5 - Prob. 71ECh. P.6 - Prob. 1QRCh. P.6 - Prob. 2QRCh. P.6 - Prob. 3QRCh. P.6 - Prob. 4QRCh. P.6 - Prob. 5QRCh. P.6 - Prob. 6QRCh. P.6 - Prob. 7QRCh. P.6 - Prob. 8QRCh. P.6 - Prob. 9QRCh. P.6 - Prob. 10QRCh. P.6 - Prob. 1ECh. P.6 - Prob. 2ECh. P.6 - Prob. 3ECh. P.6 - Prob. 4ECh. P.6 - Prob. 5ECh. P.6 - Prob. 6ECh. P.6 - Prob. 7ECh. P.6 - Prob. 8ECh. P.6 - Prob. 9ECh. P.6 - Prob. 10ECh. P.6 - Prob. 11ECh. P.6 - Prob. 12ECh. P.6 - Prob. 13ECh. P.6 - Prob. 14ECh. P.6 - Prob. 15ECh. P.6 - Prob. 16ECh. P.6 - Prob. 17ECh. P.6 - Prob. 18ECh. P.6 - Prob. 19ECh. P.6 - Prob. 20ECh. P.6 - Prob. 21ECh. P.6 - Prob. 22ECh. P.6 - Prob. 23ECh. P.6 - Prob. 24ECh. P.6 - Prob. 25ECh. P.6 - Prob. 26ECh. P.6 - Prob. 27ECh. P.6 - Prob. 28ECh. P.6 - Prob. 29ECh. P.6 - Prob. 30ECh. P.6 - Prob. 31ECh. P.6 - Prob. 32ECh. P.6 - Prob. 33ECh. P.6 - Prob. 34ECh. P.6 - Prob. 35ECh. P.6 - Prob. 36ECh. P.6 - Prob. 37ECh. P.6 - Prob. 38ECh. P.6 - Prob. 39ECh. P.6 - Prob. 40ECh. P.6 - Prob. 41ECh. P.6 - Prob. 42ECh. P.6 - Prob. 43ECh. P.6 - Prob. 44ECh. P.6 - Prob. 45ECh. P.6 - Prob. 46ECh. P.6 - Prob. 47ECh. P.6 - Prob. 48ECh. P.6 - Prob. 49ECh. P.6 - Prob. 50ECh. P.6 - Prob. 51ECh. P.6 - Prob. 52ECh. P.6 - Prob. 53ECh. P.6 - Prob. 54ECh. P.6 - Prob. 55ECh. P.6 - Prob. 56ECh. P.6 - Prob. 57ECh. P.7 - Prob. 1QRCh. P.7 - Prob. 2QRCh. P.7 - Prob. 3QRCh. P.7 - Prob. 4QRCh. P.7 - Prob. 5QRCh. P.7 - Prob. 6QRCh. P.7 - Prob. 7QRCh. P.7 - Prob. 8QRCh. P.7 - Prob. 9QRCh. P.7 - Prob. 10QRCh. P.7 - Prob. 1ECh. P.7 - Prob. 2ECh. P.7 - Prob. 3ECh. P.7 - Prob. 4ECh. P.7 - Prob. 5ECh. P.7 - Prob. 6ECh. P.7 - Prob. 7ECh. P.7 - Prob. 8ECh. P.7 - Prob. 9ECh. P.7 - Prob. 10ECh. P.7 - Prob. 11ECh. P.7 - Prob. 12ECh. P.7 - Prob. 13ECh. P.7 - Prob. 14ECh. P.7 - Prob. 15ECh. P.7 - Prob. 16ECh. P.7 - Prob. 17ECh. P.7 - Prob. 18ECh. P.7 - Prob. 19ECh. P.7 - Prob. 20ECh. P.7 - Prob. 21ECh. P.7 - Prob. 22ECh. P.7 - Prob. 23ECh. P.7 - Prob. 24ECh. P.7 - Prob. 25ECh. P.7 - Prob. 26ECh. P.7 - Prob. 27ECh. P.7 - Prob. 28ECh. P.7 - Prob. 29ECh. P.7 - Prob. 30ECh. P.7 - Prob. 31ECh. P.7 - Prob. 32ECh. P.7 - Prob. 33ECh. P.7 - Prob. 34ECh. P.7 - Prob. 35ECh. P.7 - Prob. 36ECh. P.7 - Prob. 37ECh. P.7 - Prob. 38ECh. P.7 - Prob. 39ECh. P.7 - Prob. 40ECh. P.7 - Prob. 41ECh. P.7 - Prob. 42ECh. P.7 - Prob. 43ECh. P.7 - Prob. 44ECh. P.7 - Prob. 45ECh. P.7 - Prob. 46ECh. P.7 - Prob. 47ECh. P.7 - Prob. 48ECh. P - Prob. 1RECh. P - Prob. 2RECh. P - Prob. 3RECh. P - Prob. 4RECh. P - In Exercises 5 and 6, simplify the expression....Ch. P - Prob. 6RECh. P - Prob. 7RECh. P - Prob. 8RECh. P - Prob. 9RECh. P - Prob. 10RECh. P - Prob. 11RECh. P - Prob. 12RECh. P - Prob. 13RECh. P - Prob. 14RECh. P - Prob. 15RECh. P - Prob. 16RECh. P - Prob. 17RECh. P - Prob. 18RECh. P - Prob. 19RECh. P - Prob. 20RECh. P - Prob. 21RECh. P - Prob. 22RECh. P - Prob. 23RECh. P - Prob. 24RECh. P - Prob. 25RECh. P - Prob. 26RECh. P - Prob. 27RECh. P - Prob. 28RECh. P - Prob. 29RECh. P - Prob. 30RECh. P - Prob. 31RECh. P - Prob. 32RECh. P - Prob. 33RECh. P - Prob. 34RECh. P - Prob. 35RECh. P - Prob. 36RECh. P - Prob. 37RECh. P - Prob. 38RECh. P - Prob. 39RECh. P - Prob. 40RECh. P - Prob. 41RECh. P - Prob. 42RECh. P - Prob. 43RECh. P - Prob. 44RECh. P - Prob. 45RECh. P - Prob. 46RECh. P - Prob. 47RECh. P - Prob. 48RECh. P - Prob. 49RECh. P - Prob. 50RECh. P - Prob. 51RECh. P - Prob. 52RECh. P - Prob. 53RECh. P - Prob. 54RECh. P - Prob. 55RECh. P - Prob. 56RECh. P - Prob. 57RECh. P - Prob. 58RECh. P - Prob. 59RECh. P - Prob. 60RECh. P - Prob. 61RECh. P - Prob. 62RECh. P - Prob. 63RECh. P - Prob. 64RECh. P - Prob. 65RECh. P - Prob. 66RECh. P - Prob. 67RECh. P - Prob. 68RECh. P - Prob. 69RECh. P - Prob. 70RECh. P - Prob. 71RECh. P - Prob. 72RECh. P - Prob. 73RECh. P - Prob. 74RECh. P - Prob. 75RECh. P - Prob. 76RECh. P - Prob. 77RECh. P - Prob. 78RECh. P - Prob. 79RECh. P - Prob. 80RECh. P - Prob. 81RECh. P - Prob. 82RECh. P - Prob. 83RE
Knowledge Booster
Background pattern image
Calculus
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, calculus and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Text book image
Calculus: Early Transcendentals
Calculus
ISBN:9781285741550
Author:James Stewart
Publisher:Cengage Learning
Text book image
Thomas' Calculus (14th Edition)
Calculus
ISBN:9780134438986
Author:Joel R. Hass, Christopher E. Heil, Maurice D. Weir
Publisher:PEARSON
Text book image
Calculus: Early Transcendentals (3rd Edition)
Calculus
ISBN:9780134763644
Author:William L. Briggs, Lyle Cochran, Bernard Gillett, Eric Schulz
Publisher:PEARSON
Text book image
Calculus: Early Transcendentals
Calculus
ISBN:9781319050740
Author:Jon Rogawski, Colin Adams, Robert Franzosa
Publisher:W. H. Freeman
Text book image
Precalculus
Calculus
ISBN:9780135189405
Author:Michael Sullivan
Publisher:PEARSON
Text book image
Calculus: Early Transcendental Functions
Calculus
ISBN:9781337552516
Author:Ron Larson, Bruce H. Edwards
Publisher:Cengage Learning
Use of ALGEBRA in REAL LIFE; Author: Fast and Easy Maths !;https://www.youtube.com/watch?v=9_PbWFpvkDc;License: Standard YouTube License, CC-BY
Compound Interest Formula Explained, Investment, Monthly & Continuously, Word Problems, Algebra; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=P182Abv3fOk;License: Standard YouTube License, CC-BY
Applications of Algebra (Digit, Age, Work, Clock, Mixture and Rate Problems); Author: EngineerProf PH;https://www.youtube.com/watch?v=Y8aJ_wYCS2g;License: Standard YouTube License, CC-BY