The height of the bullet when the velocity is zero is 256 ft.
<h3>Height of the bullet when the velocity is zero </h3>
The height of the bullet when the velocity is zero is determined by taking derivative of the function as shown below;

The height of the bullet at this time is calculated as follows;

Learn more about height of projectiles here: brainly.com/question/10008919
Let's use the mirror equation to solve the problem:

where f is the focal length of the mirror,

the distance of the object from the mirror, and

the distance of the image from the mirror.
For a concave mirror, for the sign convention f is considered to be positive. So we can solve the equation for

by using the numbers given in the text of the problem:



Where the negative sign means that the image is virtual, so it is located behind the mirror, at 8.6 cm from the center of the mirror.
Virtual upright and the same size
The force of friction is given by:
f = μR, where μ is the friction coefficient and R is the reaction force, which will be equal to the weight.
100 = μ x 130
μ = 0.77