This depends on the sentence given. Prepositions are words that associate an object to a certain location or position. Examples of prepositions are: on, after, below, by, during, and many more. If you want to use the word 'opportunities' as the object of your preposition, an example would be as follows:
Mary is hopefully praying for good luck as she takes on opportunities. The preposition is 'on' and the object of preposition is 'opportunities'.
Class A: Mean- 422/5= 84.4. Range: 94-74=20
Class B: Mean- 418/5= 83.6. Range: 88-80 = 8
I would help but I cant tell which clause is underline! sorry