there was a silence , as rachel and mei exchanged a look in the front seat , and amanda knew then that she was lost , that this might not be the last time she was invited to cram into rachel 's car for a let's-carpe-the unexpectedly-sunny-diem-and-have-an-impromptu-picnic/endurance-session in the park with her and mei , but the list of invitations had definitely become finite .