This year William provided $4,200 of services to a large client on credit. Unfortunately, this client has recently encountered financial difficulties and has been unable to pay William for the services. Moreover, William does not expect to collect for his services. William has written off the account and would like to claim a deduction for tax purposes. (Leave no answers blank. Enter zero if applicable.)

a. What amount of deduction for bad debt expense can William claim this year if he uses the accrual method?