P$4\mathrm{.}3-5.$ For the AM signal with m$($t$)$ shown in Fig. P$4\mathrm{.}3-5$ and $=2.$

a$)$ Find the amplitude and power of the carrier.

b$)$ Find the sideband power and the power efficiency $n.$

Figure P$4\mathrm{.}3-5.,-10$