A question about constant velocity/constant acceleration graphs?

Hey! For a lab, I have to make a few graphs, I just need some clarification.

Please correct me if I'm wrong.

For a D-T graph, where velocity is constant, the line will be straight. (Diagonal.)
For a V-T graph, where velocity is constant, the line will be straight. (Horizontal)
^ Confused about this though, at point 0 what will the y value be? (For example, if the velocity is 3m/s)
For a A-T graph, where velocity is constant, there will be NO line. (No acceleration)

For a D-T graph, where acceleration is constant, the line will be curved.
For a V-T graph, where acceleration is constant, the line will be straight. (Diagonal)
For a A-T graph, where acceleration is constant, the line will be straight. (Horizontal)??
^ For this one I am also confused.

I just need to know if I'm on the right track!
Ones in bold are the one I'm not sure are correct.

Thank you very much for reading! I appreciate any help that is offered. =)

 Quote by SoConfused__ Hey! For a lab, I have to make a few graphs, I just need some clarification. Please correct me if I'm wrong. For a D-T graph, where velocity is constant, the line will be straight. (Diagonal.) For a V-T graph, where velocity is constant, the line will be straight. (Horizontal) ^ Confused about this though, at point 0 what will the y value be? (For example, if the velocity is 3m/s)
The horizontal line will be above the horizontal axis at a distance equal to 3m/s on the scale.
 For a A-T graph, where velocity is constant, there will be NO line. (No acceleration)
The line will be horizontal and along the axis where a=0.
 For a D-T graph, where acceleration is constant, the line will be curved. For a V-T graph, where acceleration is constant, the line will be straight. (Diagonal) For a A-T graph, where acceleration is constant, the line will be straight. (Horizontal)?? ^ For this one I am also confused.
The horizontal line will be above the x axis for positive acceleration and below it for negative acceleration.
You are on the right track.

This might help
http://www.bbc.co.uk/scotland/learni...ion_rev1.shtml
 thank you for all your help :)