For many days i am unable to solve question regarding Z transform. kindly help me to calculate z transform of term which is having exp in it

for example Z transform of $\displaystyle [e^(sT/2)]/s^2$or

$\displaystyle (e^(-1.5Ts))/((s+1)(s+3))$ How to solve such questions. Kindly refer some book b/c my book does not explain it. ( s is laplace domain)

Thanks a lot for ur help