Choose the right variant of the main verb: Present Sinple or

Choose the right variant of the main verb: Present Sinple or Present Continuous
1. When...the plane...?
a. do..flying
b. is..flying
c. does flies
d. does...fly
2. Mary...to pass the exam
a. was
b. is going
c. go
d. will
3. According to schedule the bus...in an hour
a. will come
b. comes
c. come
d.came