the state or quality of being efficient.
"greater energy efficiency"
Answer
Efficiency is the ability to avoid wasting materials, energy, efforts, money, and time in doing something or in producing a desired result.
Answer:
A
Explanation:
Think about rubbing your hands together- the friciton produces heat
It is because they are both renewable sources of energy
Answer:
Intensity
Explanation:
The intensity of a sound wave is equal to the ratio between to the power emitted by the source divided by the area of the spherical surface through which the wave propagates:

where
P is the power
is the area of the spherical surface
r is the distance from the source
As we see from the formula, the intensity is inversely proportional to the square of the distance from the source:

so, intensity is the correct answer.
The slope of an object is given relative to an origin.