32.
Internal energy of a gas obeying Van-Der-Wall's equation of state, $$\left( {{\text{p}} + \frac{{\text{a}}}{{{{\text{v}}^2}}}} \right)\left( {{\text{V}} - {\text{b}}} \right) = {\text{RT,}}$$     depends upon its

34.
Feed check valve is used in steam boilers to

36.
Draft allowance given to patterns is for

38.
For which pair of the fuel gases, calorific value (C.V.) of one fuel is almost double that of the other on volume basis (i.e., kcal/Nm3) while the C.V. is same on weight basis (i.e., kcal/kg)?