$1.$ Mark's Ceramics spent $$4,000$ on a new furnace last year in the belief that it would cut annual energy usage by $25\%$ over the old furnace. This furnace is an oven that turns "greenware" into finished pottery. Mark is concerned that the new furnace requires extra labor hours for its operation. Mark wants to check the energy savings of the new oven, and also to look over other measures of their productivity to see if the change really was beneficial. Mark has the following data to work with:

$(25$ points$)$

Last Year This Year

Production $($finished units$)40004000$

Greenware $($pounds$)50005000$

Labor $($hrs$)350375$

Capital $($$$)1500019000$

Energy $($kWh$)30002600$

Were the changes beneficial based on productivity calculations?