HELP AND PLEASE PROVIDE A EXPLANATION I AM SO CONFUSED

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).

Charlie tosses five coins.what is the probability that all five coins will land tails up.

Amayoral candidate would like to know her residents’ views on a public open space before the mayoral debates. she asks only the people in her office. her co-workers are an example of a census population convenience sample simple random sample