Base elevation is 1250 ft
rate is 30 per minute 30m
so, h = 1250 - 30m
as an inclusion, 30 ft per minute is also like 0.5 per second like 1250 - 0.5s
1250/30 means it would be about 42 minutes once it touches the ground.
we have the expression

Evaluate for x=-4/5 and y=1/3
substitute the values of x and y in the given expression

the answer is 32/15
Picture?? This question is incomplete just get a picture then I can answer it