Grand Corporation reported pre-tax book income of $600,000. Tax depreciation exceeded book depreciation by $400,000. In addition, the company received $300,000 of tax-exempt municipal bond interest. The companys prior year tax return showed taxable income of $40,000. Assuming a tax rate of 21%, compute the companys current income tax expense or benefit. (Enter the answer as a positive.) Please explain step by step because I'm not getting the correct answer.

20 Ch. 6-43 Pre-tax book income Excess tax depreciation Tax-exempt interest income Net operating loss Prior year taxable income NOL from the prior year Tax Rate Current income tax benefit 600,000 (400,000) Enter as a negative (300,000) Enter as a negative (100,000) 40,000 21,000 21% 4,410 Beginning in 2018, the entire $100,000 NOL can only be carried forward and will be recorded as a deferred tax asset (benefit) of $21,000. There are no longer any carryback provisions for corporate NOL's