Shelly wants to find the speed that her dog can run. What should Shelly do? A. measure the distance the dog runs
B. measure the time the dog runs
C. measure the size of the dog and the distance it runs
D. measure the time it takes for the dog to run a certain distance

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

8 m/s because for him to get the same amount of energy as ray is putting out, bobby, who weighs half as much as ray, needs to run twice as fast.