In a packet voice communications system, a source transmits packets containing digitizedspeech to a receiver. Because transmission errors occasionally occur, an acknowledgment (ACK)or a nonacknowledgment (NAK) is transmitted back to the source to indicate the status of eachreceived packet. When the transmitter gets a NAK, the packet is retransmitted.Voice packets are delay sensitive and a packet can be transmitted a maximum ofdtimes. If apacket transmission is an independent Bernoulli trial with success probabilityp, what is the PMFofT, the number of times a packet is transmitted