When does a parabola open upward?
a.
when p is negative
c.
when p is positive
b.
when h is positive
d.
when h is negative

it opens when it is positive because , here are the informational steps :

Step-by-step explanation:

If the x is squared, the parabola is vertical (opens up or down). If the y is squared, it is horizontal (opens left or right). If a is positive, the parabola opens up or to the right. If it is negative, it opens down or to the left.

so the answer is b) opens when positive

y=3n + 1

step-by-step explanation:

this is wrong because it says the second number is one less and i added one instead

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.