Need function modules for the following...

Hello experts,

Is there an function module that I can use for:

1. get the last date for a given year

2. get the exchange rate for a given document number in a span of 5 years -

for example, I need to get the exchange rate of doc. number 0000000123

for the year 2000, 2001, 2002, 2003, 2004 and 2005(maximum of 5 years)

Help would be greatly appreciated.

Again, thank you guys and take care!