If dimensions of length are expressed as GxcYhZ =, where G, c and h are the universal gravitational constant, speed of light and Planck constant respectively, then :(i) X = (1/2), y = (1/2)(ii) x = (1/2), z = (1/2)(iii) y = (-3/2), z = (1/2)(iv) y = (1/2), z = (3/2)