<u>Harmful</u><u />
-causes heat; if it's not used correctly, it can cause injury
-when falling, the friction between your knee/leg and the ground can cause scrapes
<u>
</u><u>Helpful</u><u />
-helps stop the bike, the brakes rub against the tire which slows it down to a stop
-it can also help move the bike; the chains rub against tires which accelerate the bike
Answer:

v=343m/s
Explanation:
We have to take into account the expressions

if we assume that 256Hz is the fundamental frequency we have

and for wavelength

hope this helps!!
The gravity is pushing rhe boat down
Speed, being a scalar quantity, is the rate at which an object covers distance. The average speed is the distance (a scalar quantity) per time ratio. ... Velocity is the rate at which the position changes. The average velocity is the displacement or position change (a vector quantity) per time ratio.
Answer:
a.
Explanation:
cuz whenever the ball was traveling up the staircase it was building up energy to use (potential energy) unlike b.