Please help solve this who is right? and why

What is the point of inflection for the function f(x)=2cos4x on the interval (0, pi/2)

Atransformation was performed on rectangle c as shown in the graph. what type of transformation was performed? does that transformation result in congruent shapes? you people

Amass weighing 16 pounds stretches a spring 8/3 feet. the mass is initially released from rest from a point 2 feet below the equilibrium position, and the subsequent motion takes place in a medium that offers a damping force that is numerically equal to 1/2 the instantaneous velocity. find the equation of motion if the mass is driven by an external force equal to f(t)=cos(2t).