Which is greater: √45 or √49 – 1 ?

Which is greater: √45 or √49 – 1 ?

What value will come in place of question mark (?) in the following question?
​$$\left(9^2 \times 23 + 7^3 \times 8 + ?\right){\frac{1}{2}} = 87$$​​

The value of  $$\sqrt{361} + \sqrt{0.04} - \sqrt{6.76}$$​​

Simplify the following expression.
​$$\sqrt{12.5 \times 8 \times 2.89}$$ ​