Final answer:
The acceleration of the crate can be determined by subtracting the acceleration of the belt from the acceleration of the truck.
Step-by-step explanation:
The acceleration of the crate can be calculated by subtracting the acceleration of the belt from the acceleration of the truck. If the acceleration of the belt exceeds the value determined in part c, then the acceleration of the crate will change. In this case, the acceleration of the crate will be negative, indicating that it is moving in the opposite direction of the belt's acceleration.