Question : What is the value of

Question : Which of the following statements is correct?
I. The value of $100^2-99^2+98^2-97^2+96^2-95^2+94^2$ $- 93^2+\ldots \ldots+22^2-21^2$ is 4840.
II. The value of

Question : Which of the following statements is correct?
I. The value of $100^2-99^2+98^2-97^2+96^2-95^2+$ $94^2-93^2+\ldots \ldots+22^2-21^2$ is 4840.
II. The value of

Question : If $\frac{(17)^3+(7)^3}{\left(17^2+7^2-\mathrm{k}\right)}=24$, then what is the value of $\mathrm{k}?$

Question : Evaluate the following:
$\cos \left(36^{\circ}+A\right) \cdot \cos \left(36^{\circ}-A\right)+\cos \left(54^{\circ}+A\right) \cdot \cos \left(54^{\circ}-A\right)$