Wilbur landed his plane. the plane's elevation relative to the ground (in meters) as a function of time (in seconds) is graphed.

(image attached below)

how long was each descent by 50 meters?

a) 250 seconds
b) 10 seconds
c) 50 seconds
d) 100 seconds

The perimeter of ? cde is 55 cm. a rhombus dmfn is inscribed in this triangle so that vertices m, f, and n lie on the sides cd , ce , and de respectively. find cd and de if cf=8 cm and ef=12 cm. the answer is not cd=20 and de=15. i have tried that one, it does not work.