But at that point the price has already been paid. If you bring back rocks, or air. Same cost. If I take a first class flight, how much does it cost to take my

But at that point the price has already been paid. If you bring back rocks, or air. Same cost. If I take a first class flight, how much does it cost to take my phone? Yes I could apportion a fraction of the cost of the ticket to the phone, but most would say free. Now if the whole purpose of the flight were to get the phone from London to new York, the entire cost should be attributable to the phone, it is the reason for the journey. Was extra fuel specifically brought? Or was it just safety margin? The Landers had spare fuel when they landed, is that waste, or safety margin?