Answer:
t = [0.493,4.2]
Step-by-step explanation:
The height of the rocket straight up into the air is given by :

We need to find the interval the rocket be at least 43 feet above the ground.

So, the required interval during which the rocket is at least 43 feet above the ground is [0.493,4.2].
AE = AC = 4
m<CAB = 60 (equilateral triangle)
m<CAE = 90 (square)
m<BAE = 150 (= 60 + 90)
Triangle BAE is isosceles since AB = AE;
therefore, m<AEB = m<ABE.
m<AEB + m<ABE + m<BAE = 180
m<AEB + m< ABE + 150 = 180
m<AEB + m<AEB = 30
m<AEB = 15
In triangle ABE, we know AE = AB = 4;
we also know m<BAE = 150, and m<AEB = 15.
We can use the law of sines to find BE.
BE/(sin 150) = 4/(sin 15)
BE = (4 sin 150)/(sin 15)
BE = 7.727
The answer is the first one because 4 feet 5 inches times 40 is 176 feet and 8 inches