I'm stuck on this part in my excel spreadsheet homework: In cell B5, enter a formula using the SUM function and 3-D references that totals the Mini sales values (cell B5) in Quarter 1 from the U. S., Canada, and Mexico worksheets.
How would I solve this?

You forgot to add the possibilities. we don't know the options from which to choose.

I’d say platform as a service (paas) or application platform as a service (apaas) or platform base service is a category of cloud computing services that provides a platform allowing customers to develop, run, and manage applications without the complexity of building and maintaining the infrastructure typically associated with developing and launching an app.

The steeply sloping region of a continental margin where the sea floor descends at a rate of greater than 1 ft for every 40 feet is called. continental slope. 

The answer is yeshope this