Question for waves

1-2.
Statements B and C are correct.

3. Max speed = w^2.A
where w is the angular frequency and A is the amplitude of oscillation
hence, 1.6 = w^2.A

Max acceleration = w.A
i.e. 8.pi = w.A
Dividing, 1.6/(8.pi) = w
i.e w =0.2.pi
Period = 2.pi/w = 2.pi/(0.2pi) s = 10 s

4. From the given graph, period = 0.4 s
hence, frequecy = 1/0.4 Hz = 2.5 Hz

5. Max energy of the object = 3 J (read from graph)
Hence, by conservation of energy, max kinetic energy occurs at lowest position of the pendulum bob.
That is, max kinetic energy = 3 J