The manager of Division Z has identified labour time as the bottleneck resource in the meat skinning process of their production of kilishi. The selling price of one unit of kilishi is $30.$ Thirty minutes of labour time are required to skin $1$kg of meat to make one unit of kilishi. There are $10$ skinners available six days a week and four weeks a month. Direct material cost for one unit of kilishi is $3$ and labour cost per unit is $9.$ What is the throughput contribution per bottleneck hour? $$