In some single-celled protozoans living in fresh water, such as the paramecium, contractile vacuoles are
organelles are used to pump excess water out of the cell.
Explain why a paramecium would require contractile
vacuoles while a similar protozoan living in salt water
would not.

The table presents the average day and night temperatures in five cities. it also reveals whether a city receives substantial rainfall (wet climate) or little rainfall (dry climate). which city’s rocks are likeliest to experience frost wedging, and why? a) city a because the consistently subzero temperature would prevent water from melting b) city b because it is a wet region and the temperature fluctuates around the freezing point c) city c because it receives plenty of rain fall and the weather is moderately cool d) city d because the hot and dry weather would cause rocks to absorb water