The position of equilibrium will shift, by the addition of inert gas at constant pressure condition, in the following case(s):
a. `N_(2)(g)+3F_(2)(g) hArr 2NF_(2)(g)`, forward direction
b. `COCl_(2)(g) hArr CO(g)+Cl_(2)(g)`, forward direction
c. `CO(g)+2H_(2)(g) hArr CH_(3)OH(g)`, backward direction
d. `2C(s)+O_(2)(g) hArr 2CO(g)`, forward direction

Explanation

To determine how the position of equilibrium shifts with the addition of an inert gas at constant pressure, we need to analyze each reaction in terms of the number of moles of gas on the reactant and product sides. The key principle is that adding an inert gas increases the total volume, which decreases the partial pressures of the reactants and products. The equilibrium will shift towards the side with more moles of gas.

### Step-by-Step Solution:

1. **Analyze Reaction (a)**:
\[ N_2(g) + 3F_2(g) \rightleftharpoons 2NF_2(g) \]
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