The sum of two numbers is 21. the second number is six times the first number. work out the two numbers. write your answers on one line

Which of the following is an example of a rational number? a. π b. √ 9 c. √ 8 d. 3.8362319

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

Bob paid $3 less than tim at a local pizza parlor. together they spent $7.80. how much did bob pay for pizza?