Apulley system operates with 40% efficiency. if the work put in is 200 joules, how much useful work is produced?

1.    Efficiency is the measure of how efficient a process is. It is used to assess the ability of a process in avoiding waste energy, materials, money and time in doing a desirable output. It is calculated as;

Efficiency = useful energy ouput / total energy input

.40 = useful work / 200

useful work = 80 joules

answer: d. a cme increases the amount of energy in the solar wind

explanation:

coronal mass ejections, also called cmes, are large clouds of plasma and magnetic field that erupt from the sun. only when the cloud is aimed at earth will the cme hit earth and therefore cause impacts. high-speed solar wind streams come from areas on the sun known as coronal holes.

think its the third option