Select the correct answer.

Dan uses a remote control to make his drone take off from the ground. Function [tex]$h$[/tex] represents the height, in feet, of the drone [tex]$t$[/tex] seconds after it begins flying.

[tex] h(t)=-16(t-2)^2+64 [/tex]

Which statement correctly describes this situation?
A. The drone is on the ground at 0 and 16 seconds.
B. The drone is on the ground at 2 and 4 seconds.
C. The drone is on the ground at 0 and 2 seconds.
D. The drone is on the ground at 0 and 4 seconds.



Answer :

To determine which statement correctly describes when the drone is on the ground, we need to find the values of [tex]\( h(t) \)[/tex] at specific times [tex]\( t \)[/tex]. Let's analyze the height function given by:

[tex]\[ h(t) = -16(t-2)^2 + 64 \][/tex]

1. First, we calculate the height of the drone at [tex]\( t = 0 \)[/tex]:

[tex]\[ h(0) = -16(0-2)^2 + 64 \][/tex]

[tex]\[ h(0) = -16(4) + 64 \][/tex]

[tex]\[ h(0) = -64 + 64 = 0 \][/tex]

So, at [tex]\( t = 0 \)[/tex] seconds, the drone is on the ground ([tex]\( h(0) = 0 \)[/tex]).

2. Next, we calculate the height at [tex]\( t = 2 \)[/tex]:

[tex]\[ h(2) = -16(2-2)^2 + 64 \][/tex]

[tex]\[ h(2) = -16(0) + 64 \][/tex]

[tex]\[ h(2) = 64 \][/tex]

At [tex]\( t = 2 \)[/tex] seconds, the drone is at its maximum height ([tex]\( h(2) = 64 \)[/tex]).

3. Finally, we calculate the height at [tex]\( t = 4 \)[/tex]:

[tex]\[ h(4) = -16(4-2)^2 + 64 \][/tex]

[tex]\[ h(4) = -16(2)^2 + 64 \][/tex]

[tex]\[ h(4) = -64 + 64 = 0 \][/tex]

So, at [tex]\( t = 4 \)[/tex] seconds, the drone is on the ground again ([tex]\( h(4) = 0 \)[/tex]).

From these calculations, we see that the drone is on the ground at [tex]\( t = 0 \)[/tex] and [tex]\( t = 4 \)[/tex] seconds. This matches the statement in option D:

D. The drone is on the ground at 0 and 4 seconds.

Therefore, the correct answer is:

D. The drone is on the ground at 0 and 4 seconds.