(a) (i) State the amplitude of \(15\sin2x-5\).

(ii) State the period of \(15\sin2x-5\).

(b) The diagram shows the graph of \(y=f(x)\), where \(f(x)\) is a trigonometric function.

(i) Write down two possible expressions for the trigonometric function \(f(x)\).

(ii) State the number of solutions of the equation \(f(x)=1\) for \(-180^\circ\leq x\leq180^\circ\).