18% because take the first digits of each number and put them together lol
The x-coord. of the vertex is halfway between the given zeros. Here, it'd be halfway between x=3 and x=9, which comes out to x = 6 (answer).
2 would be the base and 3 will be the square
300° CCW is the same as 60° CW. N will show up where H is now.
The 3rd selection is appropriate.
They're all used for differentiating types of measurement in mathematics and science.