The Northland Computer Shop has decided to stop stocking assembled computers and move to assemble$-$to$-$order approach. Northland even invited customers to the work area to see their computers being assembled, a good customer relations move. The company offers seven hard disk choices, six mother boards $($including the processor$),$ five CD$/$DVD alternatives, three operations systems, and four other options. $($Show your calculations.$)$

a$.$ What is the total number of potential finished products?

b$.$ If it costs $$10$ to make a forecast each week, what is the weekly savings from forecasting just the components and options as compared the the potential number of finished products?