Answer
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Work Step by Step
The weight that the vehicle can carry depends on the number of axles. For each axle, there is a maximum weight $w$. The vehicles will be able to carry up to this weight. Hence for a $2$ axle vehicle, it is permitted to carry up to $40000$ lbs, which means any weight which is less than or equal to $40000$ is a permissible weight. The equation that represents this permissible weight will be $$w\leq40000.$$ By applying the same logic, the equation for permissible weight of a $3$ axle vehicle will be $$w\leq60000$$ and that of a $4$ axle vehicle will be $$w\leq80000.$$
