|Since this sounds like a homework assignment, we won't give you the final solution.|
We will, however, try to point you in the right direction.
Obviously you need an IF function, so the question is: What are the conditions that you need to check for?
Since you need to check for a date that is between a start date and an end date, it would be nice if Excel had a "between" function, but alas, it doesn't.
They do however, have an AND function and the ability to check check to see if one value is "less than" or "greater than" another.
Look up the AND function in Excel Help and see if you figure out how to use it for this situation.
If you have trouble figuring it out, come on back with what you've tried and we'll try to help further.
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