A company uses a two$-$step process to make a part. The first step involves a drill press that requires a $60-$minute setup time before the production of each batch can begin. After that, one unit can be drilled every $6$ minutes. The second step involves attaching the drilled item to another device which takes $8$ minutes per unit. Demand is $5$ units per hour. What is the ideal batch size of the parts? $(3$ points$)$ You must show your work.

A$)60$

B$)30$

C$)10$

D$)8$