5. You have that one correct, its scalene because all of the sides have different lengths and one angle is larger than 90 so it is obtuse.
6. This triangle is also scalene because all of the sides have different lengths. It is acute because all of the angles are less than 90.
7. No, this isn't possible. While right triangles do have two acute angles, a triangle cannot be classified as right and acute.
8. Yes, every equilateral triangle is by definition equiangular. And since they all have to be the same, it cannot be a right triangle. If it was right then there would be three right angles which would make all of the angles equal 270, and a triangle needs to have an angle sum of 180.
