A roller coaster car rapidly picks up speed as it rolls down a slope. As it starts down the slope, its velocity is 4 m/s. But 6 seconds later, at the bottom of the slope, its velocity is 46 m/s. What is its average acceleration Hurry

i think the answer is -7

Explanation:

4 - 46 = -42       -42\6 is -7  i dont know if its right

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."

rising temperatures because when water vapor in the air is cooled, it condenses. it turns back into a liquid and attaches to dust particles in the air. these very small water droplets group together to form clouds