80
81; because 92 is 81.
No but 81 is a square number
Infinitely many, since every number in that range is a square of some other number. There are 7 perfect square numbers.
80 is not a square number 1 is, 4 is, 9 is, 16 is, 25 is, 36 is, 49 is, 64 is, 81 is, 100 is 80 is not
64
It is 64.
A clown
50 80
No, there aren't any square numbers between 70 and 80. From 70 to 80, no number has a perfect square root, so no square number exists between 70 to 80.
80
It is: 80 times 50 = 4,000 square feet
It is: 50
It is: (20+80)/2 = 50
65
81; because 92 is 81.
No, 80 is a not perfect square.