a) Find the energy at the time that the charge and current have the stated values. This will be the total energy of the system, constant since there is no loss (no R) in the circuit.
b) Assume that all the energy is stored in the capacitor. To what charge does that correspond?
b) Assume that all the energy is stored in the inductor. To what current does that correspond?
d,e) Solve the equation relating q(t) and qmax at time t=0 and use the two values of charge above.