Detailed solution is shown in the image attached. The number of moles of NaCl is first obtained. Since the molarity must be in units of molL-1, the volume is divided by 1000 and the formula stated in the solution is applied and the answer is given to one significant figure.
If Star A appears to move back and forth by a greater amount than Star B, which star do you think is actually closer to you? Star A. If the parallax angle for a star is 1 arcsecond, what is the distance from the Sun to that star