It depends on what the name of the initial point is because that defines the direction of the ray. If the initial point is c, then the ray must be called cd, but if the initial point is d, then the ray must be called dc.
yes
yes they are same.
yes
The ray opposite to line CD is referred to as ray DC. A ray has a starting point and extends infinitely in one direction, so ray DC would begin at point D and extend in the direction towards point C. This means it moves in the opposite direction of ray CD, which starts at point C and moves towards point D.
If you mean CD plus DC then in Roman numerals they add up to M meaning 400 plus 600 = 1000
Yes
Yes
No. Line CD is the same as line DC, but rays are always named from the origin point, so ray DC is a ray pointing in the opposite direction from ray CD.
yes
yes
yes they are same.
yes
becasue that's the way God made it gosh!
They define the same line segment, connecting two points.
Ab and Ba are the same line because there are no endpoints to a line. Therefore, you can reverse the order of the letters. So, Cd and Dc are not the same ray because the first letter is the endpoint. So on ray Cd, point C is the endpoint and d is a point on the line coming from the endpoint. On ray Dc, D is the endpoint.
im not really sure but i know that they have a CD called hells bells
They are also called DC inhibitors