Thomas Edison is the answer im 100% sure of it.
See this. I hope you find your answer
Work = Force x Distance = 500 x 4 = 2000 Nm = 2000 J
Work= Force x Distance
Answer: 7500 Joules
This is A.) lake. A river is a small amount of water that isn't always fresh water. A stream is too small. And an ocean is made of salt water.