A study was conducted to assess the effects that occur when children are exposed to cocaine before birth. Children were tested at age 4 for object assembly skill, which was described as "a task requiring visual-spatial skills related t mathematical competence." The 196 children born to cocaine users had a mean of 7.3 and a standard deviation of 3.0. The 199 children not exposed to cocaine had a mean score of 8.3 with a standard deviation of 2.9. Assume that samples are independent simple random samples selected from normally distributed populations, and do not assume that the population standard deviations are equal. Let population 1 be children born to cocaine users. Complete b) below. a. Use a 0.01 significance level to test the claim that prenatal cocaine exposure is associated with lower scores of four-year-old children on the test of object assembly. Identify the null and alternative hypotheses. O A. Ho: H1 * P2 O B. Ho: H1 =P2 OC. Ho: 1 H2 H: H1 =2 O D. Ho: H1 =H2 H: H

A study was conducted to assess the effects that occur when children are exposed to cocaine before birth. Children were tested at age 4 for object assembly skill, which was described as "a task requiring visual-spatial skills related t mathematical competence." The 196 children born to cocaine users had a mean of 7.3 and a standard deviation of 3.0. The 199 children not exposed to cocaine had a mean score of 8.3 with a standard deviation of 2.9. Assume that samples are independent simple random samples selected from normally distributed populations, and do not assume that the population standard deviations are equal. Let population 1 be children born to cocaine users. Complete b) below. a. Use a 0.01 significance level to test the claim that prenatal cocaine exposure is associated with lower scores of four-year-old children on the test of object assembly. Identify the null and alternative hypotheses. O A. Ho: H1 * P2 O B. Ho: H1 =P2 OC. Ho: 1 H2 H: H1 =2 O D. Ho: H1 =H2 H: H

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Description: A study was conducted to assess the effects that occur when children are exposed to cocaine before birth. Children were tested at age 4 for object assembly skill, which was described as "a task requiring visual-spatial skills related to mathematical

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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