Every real machine:

a. must be more than 100% efficient
b. must be equal to 100% efficient
c. must be less than 100% efficient

No machine can operate at 100 percent efficiency because some of the energy input will always be used to overcome the force of gravity and the effects of friction and air resistance. Even an optimally tuned engine heats up eventually, and that heat is thermal energy being lost. So C. will be your Best answer.

vote read

explanation:

plate tectonics and volcanic euptions

over time, plate tectonic processes cause continents to move to different positions on the globe.

for example, britain was near to the equator 300 million years ago, and therefore was hotter than it is today. for further details look at our climate through time poster or online map.

the movement of the plates also causes volcanoes and mountains to form and these too can contribute to a change in climate.

mountain ranges formed by plate tectonics. large mountain chains can influence the circulation of air around the globe, and consequently influence the climate.   warm air might be deflected somewhere cooler by the mountains.

fkk you n*gga