this is my last set of questions if anyone could get them all completed I have 15 points on it If you could add a small explanation so I can learn from it really appreciate it :) brainliest for anyone who does all 3 questions

A80-foot piece of siding is cut into three pieces so that the second piece is four times four times as long as the first piece and the third piece is five times as long as the first piece. if x represents the length of the first piece, find the lengths of all three pieces.

If c(x) = 4x – 2 and d(x) = x2 + 5x, what is (cxd)(x)

Maria walks a round trip of 0.75 mile to school every day.how many miles will she walk in 4.5 days