Final answer:
To find the net force of a sled with a mass of 20 kg that needs to accelerate at 4 m/s², you would use the formula F = m * a. The net force required is 80 N.
Step-by-step explanation:
The subject of this question falls under Physics. To find the net force necessary for the sled to accelerate, you should use the formula for force, which is F = m * a, where 'F' is the net force, 'm' is the mass of the object, and 'a' is the rate of acceleration.
Based on the provided information, the mass ('m') of the sled is 20 kg, and the acceleration ('a') is 4 m/s². Multiply these two values to get the net force: F = 20kg * 4m/s² = 80 N. So the net force needed is 80 N (Option B).
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