Can someone help me on this?

The number of potato chips in a bag is normally distributed with a mean of 71 and a standard deviation of 2. approximately what percent of bags contain between 69 and 73 potato chips? approximately 68% approximately 71% approximately 95% approximately 99.7%

Aresearch study is studying the effects of a new drug for osteoporosis alzheimer's disease (ad) for women above the age of 65 years. a group of individuals with osteoporosis is randomized into two groups. one group is treated conventionally, and the second group is treated with the new medication. assessments are made at 3, 6, 12, 36, and 48 months. the conventionally treated group is assessed for ad using a serum blood test, and the treatment group is assessed for ad using a pet radiotracer that binds to beta-amyloid plaques. in comparing these 2 trial arms, the authors of the study may encounter which type of bias? a. selection bias on the risk of developing b. measurement bias c. confounding bias d. recall bias e. lead-time bias

Two spray paint machines are used to paint different portions of a large wall. the first machine (nicknamed "paint pro") is used for two hours. the second machine (nicknamed "goldilocks") is used for an hour and a half. when they are working at the same time, they can paint 55 square feet per minute. together they painted 5850 square feet of wall. how many square feet of wall per minute can each machine paint? e used to paint different portions of a large wall. the first machine (nicknamed "paint pro") is used for two hours. the second machine (nicknamed "goldilocks") is used for an hour and a half. when they are working at the same time, they can paint 55 square feet per minute. together they painted 5850 square feet of wall. how many square feet of wall per minute can each machine paint?