ABCD is an isosceles trapezoid with diagonals that intersect at point P. If AB||CD, AC=7y-30,BD=4y+60, and CD=5y+14, find the length of AC

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.

What is the simplified form of (3.25x10^3)(7.8x10^6) written in scientific notation?

What sums are equal to 6/12? choose all answers that are correct a.6/12+6/12+6/12+6/12+6/12+6/12 b.2/12+1/12+1/12+2/12 c.5/12+1/12 d.1/12+1/12+1/12+3/12 plz : )