Consider in Go-back-n ARQ, the sender sends frames (0, 1, 2, 3, and 4). The frames 0, 1, and 2 are sent and acknowledged in one single ACK, which arrives at the sender site after all frames have been sent. Frame 3 is received and acknowledged in a single ACK. Frame 4 is lost and resend. Draw a flow diagram depicting the scenario clearly showing timer actions and window contents.