Convert each signal to the finite sequence form {a, b, c, d, e}. \text { (b) } n \cdot u[n]-n \cdot u[n-5] \text { (c) } u[n-1] \cdot u[4-n] \text

{ (d) } 2 \delta[n-1]-4 \delta[n-3] \text { (а) } \quad u[n]-\delta[n-3]-u[n-4]