Which of the following statement is correct? I. The value of 100^2-99…

Which of the following statement is correct?

I. The value of $100^2-99^2+98^2-97^2+96^2-95^2+ 94^2 -93^2+......+22^2-21^2$ is 4840.

II. The value of $(k^2+\frac{1}{k})(k^2-\frac{1}{k})(k^4+\frac{1}{k^4})(k+\frac{1}{k})(k^4-\frac{1}{k^4})$ is $k^{16}-\frac{1}{k^{16}}$