Which statement describes why ocean currents are considered convection currents? a)warm water moves counterclockwise in the northern hemisphereb)warm water rises and cold water moves in to replace it. c)convection currents move in closed paths around the oceans. d)convection currents move in closed paths around the oceans.

I think its B B)Warm water rises and cold water moves in to replace it.

The correct answer is Option B.

Explanation:

Convection process is one of the mode of heat transfer. In this process heat transfer takes place when there is a movement of fluid (liquid or gas).

Convection occurs in ocean currents due to the heat up of oceanic waters  making it less dense. This water travel above the cooler water and thus give off its heat to the environment surrounding it. As the water cools, it then starts  to sink, and the process continues.

Convection results due to the continual circulation of ocean water. In simpler terms, warm water rises up and cold water moves in to replace it.

Hence, the correct option is B.

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

causes

fossil fuels burn

cities become more industrialized

human population grows worldwide