2. Which part of the triangle is always directly
opposite the right angle?

For any triangle, the longest side is always opposite the largest angle. The largest angle of a right triangle is always the 90 degree angle. If you had any larger angle, then the triangle wouldn't be a right triangle and instead it would be obtuse.

In a right triangle, the longest side is given the special name hypotenuse. The other sides of a right triangle are called the legs.