Better weight distribution and more stability
Answer:The frequency of the echo is slightly decreased
Explanation:
Given
speed of boat 
cliff is 
away
when boat is still , suppose t is the time taken by the echo to reach observer on the boat
But as soon as boat starts moving the distance between cliff and boat decreasing and time for echo to reach observer also decreases
and we know 
therefore frequency of the echo slightly decreased.
That's unaccelerated motion,
and constant velocity.
Answer:
Capacitor
Explanation:
A capacitor is a device that stores charges. For a sinusoidal voltage circuit which contains a capacitor, the capacitor will alternately charge and discharge at a rate determined by the frequency of the supply.
When an alternating sinusoidal voltage is applied to the plates of a capacitor in an AC circuit, the capacitor is charged firstly in one direction and then in the opposite direction changing its polarity at the same rate as the AC mains voltage.
