Final answer:
Option A: A 2-kg toy truck traveling eastward with a constant velocity of 5 m/s experiences no net external force, reflecting Newton's first law of motion.
Step-by-step explanation:
If a 2-kg toy truck is traveling eastward with a constant velocity of 5 m/s, according to Newton's first law of motion, an object in motion will stay in motion with a constant velocity unless acted upon by a net external force. Since the truck is moving with constant velocity, this implies that there is no acceleration, hence, no net external force acting on the truck. Therefore, the correct answer is (a) 0 N (no net external force).
The net external force acting on the toy truck can be calculated using Newton's second law: F = m*a, where F is the net force, m is the mass of the truck, and a is the acceleration. Since the truck is traveling with a constant velocity, its acceleration is zero, and therefore the net external force on the truck is also zero.
This means that option a) 0 N (no net external force) is the correct answer.