This is called 'trangulation'. It is used on the TV police dramas to find the location of the bad guy.
well, not a straight line. because what if you had something looking like this:
A . C .
B .
between two point there is exactly one line between three points there is exactly one plane
The two lines are identical.
Through any three noncollinear points, there is exactly one plane.
No it has two points otherwise it would just be a point you need two points to make a segment
No. A tangent touches the circle at exactly one point. A line that intersects a circle at exactly two points is a secant.
helium cannot exist as solid and thus has no melting point
No, just one point.
3 points must always be contained in one plane, as 2 make a line, it makes no difference as to where the third point is, it will exist in the same plane in the two. Aside from all three points being in a line, this is always true.
no It points to magnetic north, which is not exactly the same as true north.
Colinear points mean that if you draw a (really long) line between any two of them, the line will pass through the others. Or simply: there can exist a straight line that can pass through all of them. These are colinear points: . .... .. One line can pass through all of them: These ar not colinear points: :. If I try to connect any two of them with a line, the third point will not lie on that line.
An infinite number of lines can be drawn through a single point, but only one through two points (of course, if the points don't have the same coordinates).
A segment has two end points. If a line has one end point, then it must be called ray.