How is an annuity due similar to an ordinary annuity $($how is it different$)?$ Explain why an n$-$period annuity due is exactly the same as an $($n$-1)$ period ordinary annuity plus an extra payment at time zero. Given this, explain how you could compute the PV of an n$-$period annuity due using the normal $=$ ordinary annuity settings of a financial calculator.