A suitable system for measuring the location of events in time and space would be to have a three dimensional grid of measuring rods with a clock at each point on the grid. How should the clocks be synchronized to ensure consistent measurements?

Your answer is c. explanation: plasma  is the fourth state of matter, derived from the gaseous state of matter.  plasma  can contain free  electrons  and/or  ions. while  plasma is never neutral, it can either be positively or negatively charged.  gases, however, are electrically neutral.

The answer is a.  i hope this