Combinations of transformations: Let x[n] = anu[n], where a > 1, find and plot z[n] = x[22n].
a) z[n] = a(2n) u[2²n]
b) z[n] = a(4n) u[2²n]
c) z[n] = a(2²n) u[2²n]
d) z[n] = a(2ⁿ) u[2²n]