help me with 8 and 9 please
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Answer:
Las clases de mi colegio terminan (Or terminaron if its past tense) a las tres de la tarde. (Las clases are plural therefore you would use the Ellos/Ellas/Ustedes Conjugate of the verb)
Nueve o diez estudiantes llevan (Or "llevaron" if the its the past tense) jeans.
For the first and second sentence, it determines if your speaking in the past tense or present tense. If your quiz is mostly past tense, then use the past tense (or vice versa).