What metric unit would best measure the width of a textbook

Factor completely. 4p^2 + 36p + 81 express the answer in the form (ap + b)^2

In the given triangle, ∠aed ∼ ∠ abc, ad = 6.9, ae = 7.2, de = 5.2, and bc = 10.2. find the measure of bd and ce. round your answer to the nearest tenth.

There were 25 students who answered to a survey about sports. four-fifths of them like football. how many students like football?