It's about 10% of the tax you should have paid. At this point it doesn't make sense to worry about it since there's nothing you can do. File your taxes and pay what you owe. If there is a penalty for not paying in earlier the IRS will calculate this and send you a bill.
Depends on your state. Most states only allow licensed providers on the Food Program but an increasing number are allowing license-exempt providers to participate. Contact a local Food Program sponsor for the answer.
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