Find the sum of n terms of the sequence : 5 + 55 + 555 + …….

Calculate the ratio in which the line segment A(6, 5) and B(4, -3) is divided by the line y = 2.

Find the equations of the diagonals of a rectangle whose sides are x + 1 = 0, x - 4 = 0, y + 1 = 0 and y - 2 = 0.