No it should be "John and Sally WALK home from work." Walk should not be plural.
Creatine phosphate can supply the energy needs of a working muscle at a very high rate, but only for about 8–10 seconds.
You have to divide 3000 miles with the 5 and it gives you a velocity of 600
That is FALSE. The equation to calculate the charges has a distance component that is in the denominator which means that it is inversely proportional (as the distance os greater the force is smaller)