At the beginning of this month, the balance of nelson's checking account was $856.23. so far this month, he has received a paycheck via direct deposit of $876.25, been charged a monthly service fee from his bank of $10.00, used a debit card linked to his account to make a purchase of $23.96, written a check for $104.22 that has already been deposited, and deposited a check written to him for $25.00. what is the current balance of nelson's checking account?