TESSON 6 EXIETRISES Exercise 6A. For letters (a) and (b), write the $V(t)$ in terms of its sub-functions. For (c) and $\mathrm{d})$, express $V(t) $ in a single expression of unit step functions and sketch each waveform. (a) $V(t)=\frac{a}{b} \cdot {u(t)-u(t-b) \}$ (b) $(t)=2 \cdot {u(t-1)-u(t-2)}+3 \cdot u(t-2>$ (c) $V(t)=ts for $t>0$ (d) $V(t)=\left\{\begin{array}{1r}0 & t5\end{array} ight. $ Exercise 6B. Rewrite the following functions in a suitable way and then sketch the functions.CS.SD. 116||