X^2/xy^-4 times 2x^-3y^4/3xy^-1

Which of the following would represent the sum of 3 consecutive integers if x is the first integer?

What is sin 7x/4 ? i need on this urgent trig

Kayla wants to find the width, ab, of a river. she walks along the edge of the river 65 ft and marks point c. then she walks 25 ft further and marks point d. she turns 90° and walks until her location, point a, and point c are collinear. she marks point e at this location, as shown. (a) can kayla conclude that δ and δ are similar? why or why not? (b) suppose de = 15 ft. what can kayla conclude about the width of the river?