A certain drug has a half-life in the body of 2.0 h. Suppose a patient takes one 200. mg pill at 5:00PM and another identical pill 90 min later. Calculate the amount of drug left in his body at 8:00PM. Be sure your answer has a unit symbol, if necessary, and round it to 3 significant digits. mg ☐ x10

Marie Curie was born in Poland but studied and carried out her research in Paris. In 1903, she shared the Nobel Prize in Physics with H. Becquerel and her husband Pierre for their discovery of radioactivity. (In 1911 she received the Nobel Prize in Chemistry for the discovery of two new chemical elements, radium and polonium, the latter named for her homeland, Poland.) They and others observed that a radioactive substance could emit three types of radiation: alpha (), beta (), and gamma (). If the radiation from a radioactive source is passed between electrically charged plates, some particles are attached to the positive plate, some to the negative plate, and others feel no attraction. Which particles are positively charged, which are negatively charged, and which have no charge? Of the two charged particles, which has the most mass? Radioactivity. Alpha (), beta I(), and gamma () rays from a radioactive element are separated by passing them between electrically charged plates.

A certain drug has a half-life in the body of 2.5 h. Suppose a patient takes one 200. mg pill at 6:00PM and another identical pill 90 min later. Calculate the amount of drug left in his body at 9:00PM. Be sure your answer has a unit symbol, if necessary, and round it to 3 significant digits. mg x10 X

A woman weighs 59.0 kg and is given 720. mg pills of a drug The concentration of drug inside the patient should be no less than 3.20 mg/kg. The drug's half-life is 3.00 hours. How much time should pass between doses?