Use will,are/is going to or the present...

Question

Use will,are/is going to or the present continuous.
1.We........................(have)dinner with the smiths tomorrow night.Would you like to come?

Answer 1

We are going to have dinner with the Smiths tomorrow night.
We are having  dinner with the Smiths tomorrow night.

Answer 2

We are going to have dinner with the Smiths tomorrow night.