Answer:
Step-by-step explanation:
Given angles of elevation of 10° and 50° measured 10 seconds apart from an observation point 1.5 miles away, you want to know the vertical change in distance, and the average speed of the shuttle between the two observations.
The tangent relation tells you ...
 Tan = Opposite/Adjacent
Then the height of the shuttle at the observed angles was ...
 Opposite = Tan · Adjacent
 h1 = tan(10°)·(1.5 mi) ≈ 0.264490 mi
 h2 = tan(50°)·(1.5 mi) ≈ 1.787630 mi
The amount of vertical travel in the 10-second interval was ...
 1.787630 mi -0.264490 mi = 1.523240 mi
The space shuttle traveled about 1.523 miles vertically in the 10-second interval.
In miles per second, the average speed during that time was about ...
 (1.523 mi)/(10 s) = 0.1523 mi/s
In miles per hour, that's about ...
 (0.1523 mi/s)(3600 s/h) ≈ 548 mi/h