$1.$Three models, A$,$ B$,$ and C$,$ will be produced on a mixed$-$model assembly line. Hourly

production rate and work content time for model A are $10$ units$/$hr and $45\mathrm{.}0$ min; for model B

are $20$ units$/$hr and $35\mathrm{.}0$ min; and for model C are $30$ units$/$hr and $25\mathrm{.}0$ min. Line efficiency is

$95\%,$ balance efficiency is $0\mathrm{.}94,$ repositioning efficiency $=0\mathrm{.}93,$ and manning level $=1\mathrm{.}3.$

Determine

a$.$ How many workers and workstations must be on the production line in order to produce

this workload.

b$.$ The variable rate launching intervals for models A$,$ B$,$ and C$.$

c$.$ The fixed rate launching interval, and $($b$)$ the launch sequence of models A$,$ B$,$ and C

during $1$ hr of production.