Urgent Help Lab Due and Don't Understand it

Write a program to prepare the monthly charge account statement for a customer of CS CARD International, a credit card company. The program should take as input the previous balance on the account (the amount carried over from the preceding month) and the total amount of additional charges during the month. The program should then compute the interest for the month, the total new balance (the previous balance plus additional charges plus interest), and the minimum payment due. Assume the interest is 0 if the previous balance was 0 but if the previous balance was greater than 0 the interest is 2% of the total owed (previous balance plus additional charges). Assume the minimum payment is as follows:
new balance for a new balance less than $50
$30 plus 10% of the new balance for a new balance greater than or
equal to $50

So if the new balance is $38.00 then the person must pay the whole $38.00; if the new balance is $128 then the person must pay $42.80 ($30 + $12.80); if the balance is $350 the minimum payment is $65 (30 + 35).
In addition the program should determine if the user has exceeded the credit limit (assume the limit is $1000). If so, a message should be printed letting the user know how much over the limit he/she is and that no new charges will be accepted. The charge account statement should be printed in the following format (print the actual dollar amounts in each place using currency format from the NumberFormat class - the WaterBill.java program from lab had an example):

CS CARD International Statement
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Previous Balance: $
Additional Charges: $
Interest: $

New Balance: $

Minimum Payment: $