Stuck with my grammar advisor final exam

Hello everyone

The grammaradvisor final exam is a killer. I failed 2 times already and need a score of minimum 70. I really wanna get this because it´s good for my cv.
Well here goes

When the servers arrived, Zach gave them the information on today’s specials. He talked enthusiastically about the fresh blackberries: “They look fantastic! I want to serve them with shortcake.”

49. How many prepositional phrases are in the above passage?
One
Two
Three
Four
50. Select the sentence which is in the passive voice.
The menus were kept near the door.
The café had seating for 40 people.
Two customers were waiting when Carol opened the door.
None of these sentences use passive voice.
51. Select the sentence which is in the active voice.
The door was unlocked at 8:00.
The tables had been set by Carol.
The blueberries tasted delicious.
None of these sentences use active voice.
52. The difference between a sentence in the active voice and the passive voice
is only a matter of form.
is the relationship between the subject and the verb.
can’t be defined precisely.
All of the above
53. Select the correct statement.
Because complex and compound sentences are unusual in English,
they should only be studied by advanced students.
Because complex and compound sentences are unusual in English,
they should be encouraged in creative writing.
Because complex and compound sentences are common in English,
they should be introduced as soon as more basic forms are mastered.
Because complex and compound sentences are common in English,
they should be used even with absolute beginners.

Thank you in advance !!!