Leiff goes online to buy a new video game. he finds a site that currently has a promotion of 15% off on all orders over $50. leiff decides to buy his video game, with a price tag of $128, at this site because he knows that he will get the 15% discount when he checks out. leiff pays 5.3% sales tax on the discounted price and pays a shipping fee of $4.75. what is the total of leiff’s online purchase?

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