The equation $\left( P + \frac{a}{V^2} \right) (V - b) = \text{constant}$. The units of $a$ are:

Which of the following relations cannot be deduced using dimensional analysis? [the symbols have their usual meanings]

If velocity of light $c$,Planck's constant $h$,and gravitational constant $G$ are taken as fundamental quantities,then express length in terms of dimensions of these quantities.

The dimensions of Stefan-Boltzmann's constant $\sigma$ can be written in terms of Planck's constant $h$,Boltzmann's constant $k_B$ and the speed of light $c$ as $\sigma=h^\alpha k_B^\beta c^\gamma$. Here,

The speed of a wave produced in water is given by $v = \lambda^a g^b \rho^c$. Where $\lambda$,$g$,and $\rho$ are the wavelength of the wave,acceleration due to gravity,and density of water,respectively. The values of $a$,$b$,and $c$ are,respectively:

Assertion $(A) :$ Physical relations involving addition and subtraction cannot be derived by dimensional analysis.
Reason $(R) :$ Numerical constants cannot be deduced by the method of dimensions.