A sinusoidal signal, , is digitally created using a sampling rate producing a sample-and-hold signal, . Before any smoothing filter is applied and assuming the magnitude of at is , what is the...

A sinusoidal signal, , is digitally created using a sampling rate producing a sample-and-hold signal, . Before any smoothing filter is applied and assuming the magnitude of at is , what is the magnitude of at ? Also, find the magnitude of at and at .