The answer will be 1 because 80+80=160 not 100 so it cant be added twice so it has to be one.
Step-by-step explanation:

Answer:
<em><u>To find the biggest 4-digit number which is a perfect square, we have to take the square of biggest 2-digit number. ∴ The biggest 4-digit number which is a perfect square = 9801.</u></em>
Step-by-step explanation:
<h2>mark as brainlest answer </h2>
Answer: 0306r2
Step-by-step explanation: