Answer:
Statement 1 is true
Explanation:
As per the special theory of relativity, laws of physics do not vary with respect to all the observers who are non-accelerating and speed of light in space does not depend on the motion of observers.
Inertial frame is a reference frame which is non accelerated, i.e., the motion of the frame is at zero acceleration or constant velocity whereas a reference frame with acceleration is non-inertial.
Therefore, the linear dimension will be same in any two inertial systems.