A packet switch has four links labelled A, B, C, and D. The link lengths are: A: 1km B: 2km C: 3km D: 4km The propagation speed of all links is 0.2ms The transmission rates are : 80Mb/s. BC. 40Mb/s. Each packet is 1000 bytes. The packet switch has a fixed processing delay of 10 us. Q3: A packet arrived in the receive buffer of link A \# at time 1000.000412s and started transmission on \# link D at time 1000.000922s. \# How many packets were in the buffer of link D \# when A was added to the buffer of link D? packets = 0 Q4: Suppose that a packet is being transmitted \# on link C. 101 bits are still in the output buffer of the link. \# How many bits have already arrived in the receive buffer of the packet switch on the other end of link C? bintinativing = o