There are several information's already given in the question. Based on the given information's the answer can be easily deduced.
Base of the parallelogram = 3 1/2 feet
 = 7/2 feet
Altitude of the parallelogram = 3/4 feet
Area of the parallelogram = base * Altitude
 = (7/2) * (3/4)
 = 21/8
 = 2 5/8 square feet
I hope that this is the answer that has come to your required help.