It should be E) none of the above because:
height = 0.5
Radius = 1
diameter = 2
To write the polynomial in descending order, arrange the terms from the highest to the lowest degree. Simply base on the exponents of the variable x. You have 3, 12, 1 and 7. In descending order, that would be: 12, 7, 3 and then 1. The answer is D.
By definition, the speed is given by the quotient between the distance traveled and the time it takes to travel that distance. We have then that the expression for speed is as follows
v = d / t
where
d: distance
t: time
Substituting
v = (90feet) / (5s) = 18feets / s
answer
the average rate of the airplane model, in feet per second was 18feets / s
