## Step 1: Define the symbolic representation of the variables
The variables are ['CBRN platoons', 'airborne infantry companies', 'light infantry companies', 'armored companies']. Let's denote them as $x_0, x_1, x_2, x_3$ respectively.

## Step 2: Define the symbolic representation of the problem
The objective function to maximize is $6x_0 + 3x_1 + 5x_2 + 4x_3$.

## Step 3: List all the constraints
1. $3x_0 \geq 9$ (The total combined fun factor from CBRN platoons, and airborne infantry companies must be 9 at minimum, but since fun factor of CBRN is 3, this is directly $3x_0$)
2. $5x_1 + 3x_2 \geq 14$ (airborne infantry companies, and light infantry companies must contribute a total fuel demand of at least 14 gallons per day)
3. $4x_0 + 5x_1 \geq 9$ (The total fuel demand of CBRN platoons plus airborne infantry companies must be at minimum 9 gallons/day)
4. $3x_2 + 4x_3 \geq 9$ (light infantry companies, and armored companies must contribute a total fuel demand of at least 9 gal/day)
5. $5x_1 + 4x_3 \geq 11$ (airborne infantry companies plus armored companies must have a total fuel demand of at least 11 gal per day)
6. $3x_2 + 4x_3 \leq 21$ (The total combined fun factor from light infantry companies and armored companies has to be less than or equal to 21)
7. $3x_0 + 4x_3 \leq 29$ (The total combined fun factor from CBRN platoons and armored companies must be 29 or less)
8. $5x_1 + 4x_3 \leq 22$ (The total combined fun factor from airborne infantry companies plus armored companies must be as much or less than 22)
9. $3x_0 + 5x_1 + 3x_2 + 4x_3 \leq 22$ (The total combined fun factor from CBRN platoons, airborne infantry companies, light infantry companies, and armored companies must be 22 or less)
10. $5x_1 + 4x_3 \leq 17$ (The total fuel demand of airborne infantry companies plus armored companies must be 17 gallons per day, at maximum)
11. $3x_2 + 4x_3 \leq 28$ (light infantry companies plus armored companies must contribute no more than 28 gal per day total fuel demand)
12. $4x_0 + 4x_3 \leq 28$ (The total fuel demand of CBRN platoons and armored companies must be at maximum 28 gal/day)
13. $4x_0 + 5x_1 \leq 45$ (CBRN platoons, and airborne infantry companies has to have a total fuel demand of at most 45 gal/day)
14. $4x_0 + 3x_2 \leq 55$ (The total fuel demand of CBRN platoons, and light infantry companies must be at most 55 gal per day)
15. $4x_0 + 3x_2 + 4x_3 \leq 23$ (The total fuel demand of CBRN platoons, light infantry companies, and armored companies must be at maximum 23 gal per day)
16. $4x_0 + 5x_1 + 3x_2 \leq 16$ (CBRN platoons plus airborne infantry companies plus light infantry companies has to have a total fuel demand of at most 16 gal per day)
17. $4x_0 + 5x_1 + 3x_2 + 4x_3 \leq 16$ (The total fuel demand of CBRN platoons plus airborne infantry companies plus light infantry companies plus armored companies must be at most 16 gal/day)
18. $3x_2 + 7x_3 \leq 36$ (The total combined mobility rating from light infantry companies, and armored companies should be as much or less than 36)
19. $4x_0 + 6x_1 \leq 63$ (The total combined mobility rating from CBRN platoons plus airborne infantry companies should be at maximum 63)
20. $6x_1 + 7x_3 \leq 47$ (The total combined mobility rating from airborne infantry companies plus armored companies must be 47 at maximum)
21. $4x_0 + 3x_2 \leq 41$ (The total combined mobility rating from CBRN platoons and light infantry companies has to be 41 or less)
22. $6x_1 + 3x_2 + 7x_3 \leq 50$ (The total combined mobility rating from airborne infantry companies, light infantry companies, and armored companies should be 50 at maximum)
23. $4x_0 + 6x_1 + 3x_2 + 7x_3 \leq 50$ (The total combined mobility rating from CBRN platoons plus airborne infantry companies plus light infantry companies plus armored companies must be 50 at a maximum)
24. $x_0, x_1, x_2, x_3 \geq 0$ and are integers.

## Step 4: Create the Gurobi model
```python
import gurobi

# Create a new model
m = gurobi.Model()

# Define the variables
x0 = m.addVar(name="CBRN_platoons", vtype=gurobi.GRB.INTEGER)
x1 = m.addVar(name="airborne_infantry_companies", vtype=gurobi.GRB.INTEGER)
x2 = m.addVar(name="light_infantry_companies", vtype=gurobi.GRB.INTEGER)
x3 = m.addVar(name="armored_companies", vtype=gurobi.GRB.INTEGER)

# Define the objective function
m.setObjective(6*x0 + 3*x1 + 5*x2 + 4*x3, gurobi.GRB.MAXIMIZE)

# Add constraints
m.addConstr(3*x0 >= 9)
m.addConstr(5*x1 + 3*x2 >= 14)
m.addConstr(4*x0 + 5*x1 >= 9)
m.addConstr(3*x2 + 4*x3 >= 9)
m.addConstr(5*x1 + 4*x3 >= 11)
m.addConstr(3*x2 + 4*x3 <= 21)
m.addConstr(3*x0 + 4*x3 <= 29)
m.addConstr(5*x1 + 4*x3 <= 22)
m.addConstr(3*x0 + 5*x1 + 3*x2 + 4*x3 <= 22)
m.addConstr(5*x1 + 4*x3 <= 17)
m.addConstr(3*x2 + 4*x3 <= 28)
m.addConstr(4*x0 + 4*x3 <= 28)
m.addConstr(4*x0 + 5*x1 <= 45)
m.addConstr(4*x0 + 3*x2 <= 55)
m.addConstr(4*x0 + 3*x2 + 4*x3 <= 23)
m.addConstr(4*x0 + 5*x1 + 3*x2 <= 16)
m.addConstr(4*x0 + 5*x1 + 3*x2 + 4*x3 <= 16)
m.addConstr(3*x2 + 7*x3 <= 36)
m.addConstr(4*x0 + 6*x1 <= 63)
m.addConstr(6*x1 + 7*x3 <= 47)
m.addConstr(4*x0 + 3*x2 <= 41)
m.addConstr(6*x1 + 3*x2 + 7*x3 <= 50)
m.addConstr(4*x0 + 6*x1 + 3*x2 + 7*x3 <= 50)

# Optimize the model
m.optimize()

# Print the solution
print("Objective: ", m.objVal)
print("CBRN platoons: ", x0.varValue)
print("airborne infantry companies: ", x1.varValue)
print("light infantry companies: ", x2.varValue)
print("armored companies: ", x3.varValue)

# Symbolic representation
sym_variables = [('x0', 'CBRN platoons'), ('x1', 'airborne infantry companies'), ('x2', 'light infantry companies'), ('x3', 'armored companies')]
objective_function = '6*x0 + 3*x1 + 5*x2 + 4*x3'
constraints = [
    '3*x0 >= 9',
    '5*x1 + 3*x2 >= 14',
    '4*x0 + 5*x1 >= 9',
    '3*x2 + 4*x3 >= 9',
    '5*x1 + 4*x3 >= 11',
    '3*x2 + 4*x3 <= 21',
    '3*x0 + 4*x3 <= 29',
    '5*x1 + 4*x3 <= 22',
    '3*x0 + 5*x1 + 3*x2 + 4*x3 <= 22',
    '5*x1 + 4*x3 <= 17',
    '3*x2 + 4*x3 <= 28',
    '4*x0 + 4*x3 <= 28',
    '4*x0 + 5*x1 <= 45',
    '4*x0 + 3*x2 <= 55',
    '4*x0 + 3*x2 + 4*x3 <= 23',
    '4*x0 + 5*x1 + 3*x2 <= 16',
    '4*x0 + 5*x1 + 3*x2 + 4*x3 <= 16',
    '3*x2 + 7*x3 <= 36',
    '4*x0 + 6*x1 <= 63',
    '6*x1 + 7*x3 <= 47',
    '4*x0 + 3*x2 <= 41',
    '6*x1 + 3*x2 + 7*x3 <= 50',
    '4*x0 + 6*x1 + 3*x2 + 7*x3 <= 50'
]

print("\nSymbolic Representation:")
print("Variables: ", sym_variables)
print("Objective Function: ", objective_function)
print("Constraints: ", constraints)

```
The final answer is: 
```json
{
    'sym_variables': [('x0', 'CBRN platoons'), ('x1', 'airborne infantry companies'), ('x2', 'light infantry companies'), ('x3', 'armored companies')], 
    'objective_function': '6*x0 + 3*x1 + 5*x2 + 4*x3', 
    'constraints': [
        '3*x0 >= 9', 
        '5*x1 + 3*x2 >= 14', 
        '4*x0 + 5*x1 >= 9', 
        '3*x2 + 4*x3 >= 9', 
        '5*x1 + 4*x3 >= 11', 
        '3*x2 + 4*x3 <= 21', 
        '3*x0 + 4*x3 <= 29', 
        '5*x1 + 4*x3 <= 22', 
        '3*x0 + 5*x1 + 3*x2 + 4*x3 <= 22', 
        '5*x1 + 4*x3 <= 17', 
        '3*x2 + 4*x3 <= 28', 
        '4*x0 + 4*x3 <= 28', 
        '4*x0 + 5*x1 <= 45', 
        '4*x0 + 3*x2 <= 55', 
        '4*x0 + 3*x2 + 4*x3 <= 23', 
        '4*x0 + 5*x1 + 3*x2 <= 16', 
        '4*x0 + 5*x1 + 3*x2 + 4*x3 <= 16', 
        '3*x2 + 7*x3 <= 36', 
        '4*x0 + 6*x1 <= 63', 
        '6*x1 + 7*x3 <= 47', 
        '4*x0 + 3*x2 <= 41', 
        '6*x1 + 3*x2 + 7*x3 <= 50', 
        '4*x0 + 6*x1 + 3*x2 + 7*x3 <= 50'
    ]
}
```