Найти найменьший простий дильник числа 87.

Помогите пожалуйста с английским...

1. Since then the monster ... at least once a year.

a) saw; b) has been seen; c) has seen; d) in being seen

2. The doctor asked how long ... the medicine.

a) would I take; b) I had been taking; c) had taken; d) I took

3. I can give you this book. You ... go to the library.

a) wouldn't; b) needn't c) may not; d) can't

4. The news made Jon ... .

a) laugh; b) to laugh; c) laughing; d) laughed

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