Final answer:
The subject of this question is Physics, specifically relating to the concept of speed. The student is asking about the speed of a golf ball moving at 31.3 m/s (70 miles per hour) with a mass of 4.50×10-2 kg.
Step-by-step explanation:
The subject of this question is Physics, specifically relating to the topic of speed. In this question, the student is asking about the speed of a golf ball moving at 31.3 m/s (70 miles per hour) with a mass of 4.50×10-2 kg. To calculate the speed of an object, we can use the formula: speed = distance/time. In this case, we are given the speed and the mass of the golf ball, so we can compare it to other examples provided to better understand the concept of speed.