In order to solve this problem, more context is needed, such as the height from which the rock is dropped and any given time values or initial velocities.

Here’s how we would typically approach the two parts:

(c) Average velocity of the rock during its fall:

The average velocity $v_{avg}$ for an object in free fall can be found using: $v_{avg} = \frac{v_i + v_f}{2}$ where:

• $v_i$ is the initial velocity (which is often 0 if the object is dropped from rest),
• $v_f$ is the final velocity just before hitting the ground.

If the object is dropped from rest, then $v_i = 0$, so the average velocity simplifies to: $v_{avg} = \frac{v_f}{2}$

(d) Final velocity when the rock hits the ground:

To find the final velocity $v_f$, we use the following kinematic equation: $v_f = \sqrt{2gh}$ where:

• $g$ is the acceleration due to gravity (approximately $9.8 \, \text{m/s}^2$),
• $h$ is the height from which the rock was dropped.

Once we know $v_f$, we can plug it into the average velocity formula for part (c).

Please provide the height of the fall or any additional details if available, so I can calculate the exact values for you.

Let me know if you want more details on the calculations! Here are 5 follow-up questions based on this:

1. What is the value of the height the rock falls from?
2. Was the rock dropped from rest or given an initial velocity?
3. How long does the rock take to hit the ground?
4. How would you calculate the average velocity if the initial velocity were not zero?
5. What is the significance of air resistance in real-world falling objects?

Tip: Always check the units of all the quantities to ensure the correct outcome in physics problems.