A ray is part of a line which is finite in one direction, but infinite in the other.
2 rays
Six angles.
There is 1 angle between each pair of rays. So 30 rays equals 30 angles. But, if the angles are likened to the spokes of a bicycle wheel, should the 30 rays not completely fill the circumference of the wheel, the 2 outer rays also form an angle. So the possible total is 31 angles.
10 rays can meet in 45 vertices. At each such vertex there will be 4 angles which makes 180 angles in all.
Vertical angles
they are vertical angles
if the rays have no common points, the answer is zero. if the rays all have the same end point, the answer is 21 -- counting only the acute angles.
900
because they are
I don't think there are rays of naming. Angles are made up of 2 rays.
Yes, the opposite rays of vertical angles are always coplanar, so the angles are as well.
An angle is formed by two rays with a common endpoint.