Planck's constant (h), speed of light in vacuum (c) and Newton's gravitional constant (G) are three fundamental constants. Which of the following combinations of these has the dimension of length ?

If dimensions of critical velocity $$\upsilon $$_c of a liquid flowing through a tube are expressed as $$\left[ {{\eta ^x}{\rho ^y}{r^z}} \right]$$ where $$\eta ,\rho $$ and r are the coefficient of viscosity of liquid, density of liquid and radius of the tube respectively, then the values of x, y and z are given by

If energy (E), velocity (V) and time (T) are chosen as the fundamental quantities, the dimensional formula of surface tension will be

If force (F), velocity (V) and time (T) are taken as fundamental units, then dimensions of mass are