Answer:
C. His estimate is incorrect; it should be closer to 12 than 11.
Step-by-step explanation:
1. 11^2 is 121, √(140^2) is 140, and 12^2 is 144.
2. Based off these numbers 140 is closer to 144, meaning that √(140) is closer to 12 than 11.
Therefore, the correct answer is C. His estimate is incorrect; it should be closer to 12 than 11.
