I believe the answer you are looking for is the excretory system.
True seems like the best answer. Players have trouble with the reverse swinging motion. The grip change of the racquet is more than likely the reason. There is more than one kind of backhand stroke.
If you ran in place for 20 minutes and stop every 5 mins then your heart rate will be in your target zone
Sometimes breaking down a question helps us answer the question. The general question to be answered here is "What is 2/3 of 7/8?". We can solve this by multiplying the fractions together. 2/3 times 7/8 gives us 7/12.
