Answer:
3. velocity is zero.
Explanation:
The velocity of a simple harmonic motion is given by

Here, <em>ω</em> is the angular velocity, <em>A</em> is the amplitude (or maximum displacement from the equilibrium point) and <em>x</em> is the displacement at any time.
At maximum displacement, <em>x </em>=<em> A</em>.<em> </em>Then

Therefore, at maximum displacement, velocity is 0.
Practically, this can be observed in a simple pendulum. As it approaches the maximum displacement, its velocity reduces. It becomes zero at this point and then reverses as the pendulum changes course. Then the velocity begins to increase. It becomes maximum at the equilibrium point but once past that, the velocity begins to reduce as it approaches the other amplitude.
For acceleration,

It follows that at maximum displacement, the acceleration is a maximum. The negative sign indicates that it is in an opposite direction to the displacement. Both kinetic energy (
) and linear momentum (
) are proportional to velocity; they are therefore both zero at the maximum displacement.
From the definition of average velocity,
,
and the fact that constant acceleration means

we can solve for the time
:

It takes him
t = 16 miles / 156 mph = 0.1 hours
the shadows are exactly the same length in the morning as they are in the evening.
is so obvious it’s that when the sun is low you get long shadows and when the sun is up in the sky like in the noon the shadow is shorter.