Where can the perpendicular bisectors of the sides of a right triangle intersect?
i. inside the triangle
ii. on the triangle
iii. outside the triangle

Perpendicular bisectors would intercept inside the triangle. A perpendicular bisectors is a line that bisects each side of the triangle and is perpendicular to it, so if you picture it in you head, you can see that they intercect inside the triangle.

It would be 1 because perpendicular bisectors are always inside the triangle

The probability of picking 2 green markers is 2/10