Answer:
Sound travels through solids and liquids at the same speed
Explanation:
Because sound needs a dencer object to travel fast and since both liquid and solids are closer than gas sound travles faster in them.
First,
where 
is density, 
is mass, and 
is volume. We can compute the volume of the roll:
When the roll is unfurled, the aluminum will be a rectangular box (a very thin one), so its volume will be the product of the given area and its thickness 
. Note that we're assuming the given area is not the actual total surface area of the aluminum box, but just the area of the largest face (i.e. the area of one side of the unrolled sheet of aluminum).
So we have
where 
is the given area, so
If we're taking significant digits into account, the volume we found would have been 
, in turn making the thickness 
.
Answer:
its The rolling friction is greater than the force of the car’s weight against the hill.
and A force was required to start the car rolling.
Explanation:
