After 4 days, a bookstore has 140 copies of a new title still on hand. After 9 days, the bookstore has 50 copies still on hand. Model this situation by writing an equation of the form c(t)=mt+b where c is the number of copies still on hand after t days of being available.

Aresearch company wants to test the claim that a new multivitamin to improve short term memory. state the objective of the experiment, suggest a population, determine the experimental and control groups, and describe a sample procedure.

According to the 2008 u. s. census, california had a population of approximately 4 × 10^7 people and florida had a population of approximately 2 × 10^7 people. which of the following is true? a. the population of florida was approximately two times the population of california. b. the population of florida was approximately twenty times the population of california. c. the population of california was approximately twenty times the population of florida. d. the population of california was approximately two times the population of florida.

Me. i can't figure out this question. give an explanation too. .