Why is it now a challenge to use phone numbers for drawing a simple random sample?

a. some people only have cellphones
b. some people have cellphones and landlines, so could be called twice
c. phone numbers are now portable so area codes do not always correspond to location
d. all of the above

(least common multiples) the answer that i had in the 1st step was lcm of airline tickets sold=72. idk if that even matters but just in case. ! three co-workers are busy selling airline tickets over the phone. in an 8-hour day, charles can sell 8 airline tickets, ann can sell 9 airline tickets, and michelle can sell 6 airline tickets. step 2 of 2: what is the smallest number of 8-hour days needed for each of them to achieve the same number of sales? it takes charles . it takes . it takes .

*segment an is an altitude of right ? abc with a right angle at a. if ab = 2root 5 in and nc = 1 in, find bn, an, ac.

Write the percent as a fraction or mixed number in simplest form. 0.8%