How to find x and y in a special right triangle equations?

Corresponding angles are a. always b. sometimes c. never congruent

Question 2 (essay worth 10 points) (03.02 mc) in δabc shown below, point a is at (0, 0), point b is at (x2, 0), point c is at (x1, y1), point d is at x sub 1 over 2, y sub 1 over 2, and point e is at the quantity of x sub 1 plus x sub 2 over 2, y sub 1 over 2: triangle abc is shown. point d lies on segment ac and point e lies on segment bc. a segment is drawn between points d and e. point a is at the origin. prove that segment de is parallel to segment ab.

The diameter of the moon is about 3500 km. approximate the surface area of the moon using the formula for the surface area of a sphere, s = 4πr^2. write your answer in scientific notation.