1-)

Let y(t) = -r(t+1) + 2r(t) +u(t) - u(t-4) - r(t-1) - r(t-2) + r(t-3)

Plot y(t)

Plot y(t)'

Plot z= y(0.5t-1)

2-)

Let x(t) = u(t+1) - u(t-1) and y(t) = u(t) + u(t+2) -2u(t-4)

Plot x(t) and y(t)

Evaluate graphically and plot z(t)=x(t)*y(t)

3-)

Find all the complex numbers z such that

z=(68j) ^ 4/3

Give your answer in rectangular form