Let y(t) = r(t)-r(t-1)-r(t-2)+2г(t-3)-r(t-4)-u(t-4), where r(t) is the ramp function. a) plot y(t)
b) plot z(t) =y(2t-1)
c) plot y (t)
d) calculate the energy of y(t) note: r(t)=t for t≥0 and 0 for t<0