Anew bank offers you a 0% intro apr on balance transfers. all transfers must be completed in first 4 months. after that the variable apr will be 24%, based on your credit score remaining above 650. if you transfer a balance with this offer, after your 0% intro purchase apr expires, both new purchases and unpaid purchase balances will automatically accrue interest until all balances, including your transferred balance, are paid in full. you have transferred $600 to this account and paid half before the fourth month. you then charge $350 in the fifth month. what is your balance at the end of the fifth month if you have made no additional charges, payments or transfers?

a) $600
b) $663
c) $850
d) $2,475