Limits question plz help

At the olympic games, many events have several rounds of competition. one of these events is the men's 100-meter backstroke. the upper dot plot shows the times (in seconds) of the top 8 finishers in the final round of the 2012 olympics. the lower dot plot shows the times of the same 8 swimmers, but in the semifinal round. which pieces of information can be gathered from these dot plots? (remember that lower swim times are faster.) choose all answers that apply: a: the swimmers had faster times on average in the final round. b: the times in the final round vary noticeably more than the times in the semifinal round. c: none of the above.

How long must $542 be invested at a rate of 7% to earn $303.52 in interest? in a easier way

Secant ac and bd intersect at point e inside f what is the measure of aed if measurements cd equals 30 a b is 50 and cb is 170