Is "which" the right word here?

[Jobs]

I need help with this one:

"There are a number of additional variables which impacts would be interesting to test, ..."

 

[emsr2d2]

I need help with this one:

"There are a number of additional variables which impacts would be interesting to test, ..."

Yes, but you need a different construction and more words:

There are a number of additional variables, the impacts of which would be interesting to test.