How far away is it and how long will we be gone?

Arin went downstairs to have orange juice and I began to panic after he didn´t return in several hours.  He finally has arrived and I should have known, he was invited to visit a friend´s house a couple kilometers from here.  7 hours later, here he is.  We must remember to ask, not only how far we are going, but how long will we be gone.