Final answer:
The differentiation between fact and opinion is crucial, with the former being based on verifiable evidence and the latter on personal beliefs. Multi-cellular organisms consist of many specialized cells, whereas uni-cellular organisms are single-celled. 'Frequently' denotes a high occurrence rate, while 'rarely' indicates something happens seldom.
Step-by-step explanation:
The difference between fact and opinion is fundamental in understanding information. A fact is a statement based on objective reality, and can be proven with evidence. On the other hand, an opinion reflects personal beliefs or feelings and can vary from person to person.
Concerning the difference between multi-cellular and uni-cellular organisms, a multi-cellular organism consists of multiple cells that may be specialized and work together, while a uni-cellular organism is made up of a single cell. This single cell performs all the necessary functions for the organism's survival.
The terms frequently and rarely denote frequency. Frequently means something happens often, while rarely implies that it occurs seldom.