Calculate the total time required to transfer a 1000-KB (KB: Kilo-Byte) file in the following cases, assuming a Round Trip Time (RTT) of 50ms, a packet size of 1KB, and an initial 2*RTT of handshaking to establish the connection before data is sent (2 points):a) the bandwidth is 1.5Mbps (million bits per second), and data packets can be sent continuously. b) the bandwidth is still 1.5Mbps, but we use a protocol with ACK to improve reliability. After we finish sending each data packet we must wait one RTT to receive ACK before sending the next.