A solid hemisphere has a radius of 7 cm. Find the total surface area.

Find the value of a if the line 2y - ax + 4 = 0 is perpendicular to the line y + (x/4) - 7 = 0

The locus of a point P which is equidistant from two given points S and T is

Find the mean of the data: 7, -3, 4, -2, 5, -9, 4, 8, -6, 12

The range of the data: k+2, k-3, k+4, k-2, k, k-5, k+3, k-1, and k+6 is