Please help me with this networks problem, thank you!

Consider a source that is sending on/off traffic (as in a square wave). In particular, for 0.5 seconds, it sends data traffic at a rate of 12 Mbps then it does not send any data traffic for 2 seconds. This process repeats. If this traffic is going through a router that has 10 Mbps capacity and a buffer of size B bits. Answer the following questions [2 pts each] (a) What is the average throughput achieved by this source? (your answer should be in Mbps) (b) How large B should be to prevent any data loss (that is to accommodate each square burst and buffer it)? (c) If we would like to remove this buffer, but still would like the source to send the same amount of data per burst, how would you choose the on period and the data rate