The first square is 40 square feet because 8 x 5 = <<8*5=40>>40
The second square is 70 feet because 10 x 7= <<10*7=70>>70
The third square is 25 feet because 5 x 5 = <<5*5=25>>25
The total square footage is 135 feet because 40 + 70 + 25 = <<40+70+25=135>>135
The flag will be 9 feet tall because 135 / 15 = <<135/15=9>>9
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