Answer :
1) C (after she finishes her homework), as an adverbial phrase is a phrase which changes the time, place, or manner of a verb, in this case the time Andrea will go to the store.
2) B (The teachers had a race grading papers; neither one of them won.), as this properly uses the semicolon, which is used to combine two phrases which could each function as their own sentence.
3) D (The girls liked riding bikes; on the other hand, they loved riding roller coasters.), as it properly uses the semicolon on two phrases and properly uses the conjunctive adverb (on the other hand), which must be used after a semicolon/period to connect two phrases/sentences.
2) B (The teachers had a race grading papers; neither one of them won.), as this properly uses the semicolon, which is used to combine two phrases which could each function as their own sentence.
3) D (The girls liked riding bikes; on the other hand, they loved riding roller coasters.), as it properly uses the semicolon on two phrases and properly uses the conjunctive adverb (on the other hand), which must be used after a semicolon/period to connect two phrases/sentences.