Which form shall I use?

Hi))

I need some help with the sentences. What shall I write in the place instead of the dots ( 4 possible alternatives are given: Simple Present/Present Continuous/ going to/will

1.

A: Why did you call your grandma?

B: I........( visit) her at the weekend.

2.

I've got the plane tickets. I .....( fly) on Monday.

3.

A: Whose is that night dress?

B: It's mine. I.........(wear) it at John's graduation party.