For each of the production functions

1.f (K,L)=2K +L

2.f (k,L)=min{2K,K +L}

3.f (k,L)=K +min{K,L}

4.f (K,L)=max{K,2L}

write down and solve the cost minimization problem of a firm with that technology of production subject to producing at least q units