What is the recommended stock of coal? Which office suppliers are they going to use?

M: Jane. shall we go through the inventory then? Let’s start with coal.
F: We have about 45 tons. But we are supposed to have 70 tons.
M: So we’ve got too little. We’d better order some more. How about gas?
F: I think we have enough stock for that.
M: OK, thank you then.

M: This latest order from Office Network is very expensive. Have you thought about changing suppliers?
F: Well, I did think about it. But Excel Products wouldn’t give us any discount and A-Grade Service wants cash on delivery, so let’s just leave things as they are.