Rationing is an attempt to limit shortages that naturally result from what?

What are the similarities of physical and chemical change ?

How does the principle of electromagnetism explain the interaction between earth’s magnetic field and the solar wind?

6. using 3 – 4 sentences explain (in your own words) why water expands when it freezes? 7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation.