If npgreater than or equals5 and nqgreater than or equals5, estimate Upper P (at least 6 )with nequals13 and pequals0.4 by using the normal distribution as an approximation to the binomial distribution; if npless than5 or nqless than5, then state that the normal approximation is not suitable.

the height of the surface increases from the center out to the sides of the road.

step-by-step explanation:

as we move out we move away from the x-axis.

and as mentioned in the problem statement that height of a road increases when we move away from the center x.

hence proved that 3rd option

the height of the surface increases from the center out to the sides of the road.

is the correct option.