The$$ three$-$station work cell illustrated in the figure below has a product that must go through one of the two machines at station $1($they are$$ parallel$)$ before proceeding to station $2.$

Station $1$

Machine A

Station $1$

Machine B

Station $2$

Station $3$

Capacity: $20$ units$/$hr

Capacity: $20$ units$/$hr

Capacity:

$12$ units$/$hr

Capacity:

$3$ units$/$hr what is the throughout time?