I seem to remember learning a rule that the following sentence should be written like this (because of the conjunction "and") :
The future strength AND long-term stability of our company ARE rooted in a disciplined risk management strategy.
However, I'm seeing the singular 'is" used a lot in the company I work for:
The future strength AND long-term stability of our company IS rooted in a disciplined risk management strategy.
My question is whether or not they are both acceptable?