Samsung is a manufacturer of smartphones. They make $60,000$ smartphones per month with the following resources. Their Labour takes $160$ hours at $$25$ per hour and uses raw material worth $40,000$ pounds $($lbs$)$ that costs $$3\mathrm{.}5$ per pound $($lbs$).$ Their operational overhead expense $$15,000$ and their capital cost to complete the production is valued at $$20,000.$

What is their Single Factor Productivity?

Excel not required for this calculation.

a$.325$

b$.375$

c$.450$

d$.425$

e$.300$