$.$A company signed an export contract based on CFR with B company for $3000$ tons wheat. A company loaded $5000$ tons wheat in bulk on board and asked the shipping company to assign $3000$ tons to B company at the port of destination. After the completion of the loading, A company sent out the shipping advice. During the transportation, the vessel met with a mishap and $3000$ tons wheat got lost, only $2000$ tons wheat arrived the port of destination.When B company wanted to pick up the goods at the port of destination, A company told them all their goods had been lost and risk of the goods had been transferred to B company when the goods were shipped on board of the vessel at the port of shipment, so A company born no responsibility for the loss.Question:$1.$Do you think A company could be exempted from the responsibility?$2.$Why?