How to solve these questions in finance?

Question

1) Sally completes her degree in 2009. her parents decide to give her a lump sum to finance her education. She intends to withdray $800 at the beginning of each semester over 4 years of her degree. Each semester begins 1 feb and 1 aug, The funds are placed into a saving acount that pays 8.5%p.a compounded semi-annually. How much do sally's parents deposit of 1 feb 09 to enable her to withdraw each semseter for the necxt 4 years, with first withdrawal to be on that date.

2) sally's sister( jill) is 6yrs younger. her parents decide to put another lump son into the same account to finance education. They will deposit funds on 1 feb 09 the year jill commences high school. to allow for inflation they want jill to be able to withdraw 1000 at beginning of each semester whn she starts uni. how mch will they need to deposit

Answer 1

1) $5,557.56

2) $4,979.47 more, for a total of $10,537.03