how to write Formula in excel

Hi,

I need help regarding excel formula for incremental bonus value.

Example: fix bonus is 1000 any Qtr

x 

if 1st Qtr target fulfilment is more than 100 then x person get Rs.3000/-in 1st Qtr

if 1st & 2nd Qtr target fulfilment is more than 100 then x person get extra Rs.500 in 2nd Qtr

if 1st, 2nd & 3rd Qtr Target fulfilment is more than 100 then X person get extra 1000 in 3rd Qtr

if all qtr target fulfilment is more than 100 then X person get extra 1500 in 4th Qtr

But 

but X person does fulfil his target in 2nd Qtr then he gets only fix amount.

then start from 3rd Qtr again.

means continuously x person meet their target he will get Rs.500 extra.

please Help