What should come in place of the question mark (?) in the following questions?
$$(45)^{2} + (21)^{2} = (?)^{2} + 257$$
$$90780\div\sqrt{?}=85\times12$$
$$1862 \div 28 = ?$$
63% of 962 + ? = 999
743 + 958 = ? % of 5670
$$\sqrt{5929}=?$$
$$638 + 254 \div 8 \times 4 = ?$$
$$65\% of 400 + \sqrt{?} = 40\% of 800 - 12\% of 400$$
$$\frac{18\times14+46}{16\times10-23}=?$$
$$8 \times 5 + (?)^{2} = (11)^{²}$$