Question

Please help!
f(θ) & g(θ) are both sine functions , where f(0) = g(0) = 0.The amplitude of f(θ) is twice the amplitude of g(θ). The period of f(θ) is one-half the period of g(θ). If g(θ) has period of 2pi and f = pi/4=4, what is function rule of g(θ)