they are called "cells"
hope this is the answer is what your looking for.
Answer:
Please check the attached file for the diagram
Explanation:
The velocity of the of the rowboat
through the river is the resultant velocity. It is obtained taking a vector sum of the velocity in still water and the velocity of the river.
There are several ways to take this vector sum, but the question makes it simple for us to use Pythagoras's theorem because the East and North directions are perpendicular to each other.
Hence;


Answer:
Explanation:
Given
initially mass is stretched to 
Let k be the spring Constant of spring
Therefore Total Mechanical Energy is 
Position at which kinetic Energy is equal to Elastic Potential Energy


it is given

thus 


