Check the picture below, the height there uses feet, but nevermind that, we can simply let it be meters, like in this case.
how hight does it go? well, that'd be the y-coordinate of the vertex.
how long does it take? well, that'd be the x-coordinate of the vertex.
Answer:
10cm correct to nearest cm" means the diameter could be arbitrarily close to (but less than) 10.5 cm. So the maximum possible circumference is 10.5π cm.
"10cm correct to nearest cm" also means that the diameter could be arbitrarily close to (but greater than) 9.5 cm. So the minimum possible area is π(9.5)²/4 cm²
The answer is a) the slope is undefined
I'm sure the correct answer is 3k-2