You are sending a 500KB file to a destination 20km away. The channel data rate is 100Mbps and the propagation speed is 2.4 x 10⁸ ms⁻¹. Each data frame carries 1400 bits of data plus 50 bits of overhead. What is the approximate total time required to transmit the entire file?
a) 0.1 milliseconds
b) 10 milliseconds
c) 1 second
d) 10 seconds