As your heart grows stronger from exercise, your resting heart rate will become

higher
inefficient
lower
non-existent

Higher

Explanation:

As your heart grows stronger it is able to pump more blood and oxygenate more of the muscles in your body. It increases the heart rate, but not to an unhealthy extent.

onto a large boat, and mark the water level that the boat sinks to. then, take the elephant out and put a bunch of marked weights onto the boat until it reaches the same water level. add up the masses of the weights to get the weight of the elephant.

the answer is "a" although apex might say best book of the year.