Numeric Simplification Test 2

1.What should come in place of the question mark (?) in the following question?

2 – [6 – {3 + (-4 + 5+ 1) × 8} + 12]=?

 Find the square root of 902500?

 Find the square root of 12544?

What is the answer of:

8.6 × 8.6 + 2 × 8.6 × 4.2 + 4.2 × 4.2