Determine the minimum required sample size if you want to be 95% confident that the sample mean is within 21 units of the population mean given o = 97.9. Assume the population is normally distributed.
What is the critical value that corresponds to a level of confidence of 9595?
Round your answer to two decimals.
What is the minimum sample size required for this problem?
Round your answer up to the next integer

Aculture started with 2,000 bacteria. after 8 hours, it grew to 2,400 bacteria. predict how many bacteria will be present after 19 hours . round your answer to the nearest whole number. p=ae^kt

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

Simplify each expression for 18, 20, and 21