3. The sample variance of n measurements x1,,xn can be computed as either n1i=1n(xix)2,wherex=ni=1nxi, or n1i=1nxi2(i=1nxi)2. Find and compare the number of divisions, multiplications, and additions/ subtractions (additions and subtractions are usually bunched together) that are required for computing the variance according to each of these formulas