Identify a potential source of bias (if any). using random digit dialing, 1599 people were called and asked what obstacles (such as childcare or long hours at work) kept them from exercising. (source: yankelovich partners, inc. for shape up america! )

Prove that the sum of two consecutive exponents of the number 5 is divisible by 30.if two consecutive exponents are 5n and 5n + 1, then their sum can be written as 30.

You drop a rubber ball off the roof of a 50 meter high building onto a paved parking lot. it bounces back up with every bounce, but not quite all the way back up to you. after the first bounce it bounces back only 80 percent of the distance it was dropped from. the pattern continues, meaning after every bounce it comes up to just 80 percent of the previous maximum height. so if before the first bounce the height is 50 meters, what height does the ball reach after the fifth bounce? round your answer to one decimal place and chose the correct response from the choices below:

An ulcer medication has 300 milligrams in 2 tablets. how many milligrams are in 3 tablets?