(a) For the work-energy theorem, the work done to lift the can of paint is equal to the gravitational potential energy gained by it, therefore it is equal to
where m=3.4 kg is the mass of the can, g=9.81 m/s^2 is the gravitational acceleration and 
is the variation of height. Substituting the numbers into the formula, we find
(b) In this case, the work done is zero. In fact, we know from its definition that the work done on an object is equal to the product between the force applied F and the displacement:
However, in this case there is no displacement, so d=0 and W=0, therefore the work done to hold the can stationary is zero.
(c) In this case, the work done is negative, because the work to lower the can back to the ground is done by the force of gravity, which pushes downward. Its value is given by the same formula used in part (a):
ANSWER
Velocity of the mass reaches zero
EXPLANATION
We want to identify what hapens to a mass attached toa a spring at maximum displacement.
When a mass attached to a spring is at its maximum position of displacement, the direction of the mass begins to change. This implies that the velocity of the mass will reach zero.
Hence, at maximum displacement, the velocity of the mass reaches zero.
A transverse wave is a wave where the particles in the medium move perpendicular (at right angles) to the direction of the source or its propagation (think of a snake slithering through grass) an example of a transverse wave could be a light wave. Light waves for instance don’t need a medium in order to propagate but transverse waves in general do need a medium.
