Paramecium are single cell eukaryotes that live in fresh (pure) water. They have a vacuole that contracts to expel excess water that enters the cytoplasm. Eukaryotes that live in salt water do not need these vacuoles because * 1. there is more solute inside their cytoplasm than outside it
2. there is the same amount of solute outside their cytoplasm as in it
3. salt will not enter their cytoplasm
4. water can't cross their cell membrane

C >-< sorry if its wrong im like 65% sure

Explanation: im think its C due to the fact that salt water nor any kind of water goes into cytoplasm.

in the year 2850, humans successfully colonized mars. the martian modules that were constructed could hold only a small population of people. it is now a century later, and the population on mars has grown to 600 people. of the current mars population, 45 people express the recessive phenotype for phenylketon- uria (pku) syndrome (pp genotype).

explanation: