An ac generator has emf = m sin (w d t = /4), where m = 30.0

An ac generator has emf ξ = ξ m sin (w d t = π/4), where ξ m = 30.0 V w d = 350 rad/s. The current produced in a connected circuit is i (t) = I sin (w d t = 3π/4), where I = 620 mA. At what time after t = 0 does
(a) The generator emf first reach a maximum and
(b) The current first reach a maximum?
(c) The circuit contains a single element other than the generator. Is it a capacitor, an inductor,
or a resistor? Justify your answer.
(d) What is the value of the capacitance, inductance, or resistance, as the case may be?