Hey guys i got this question to answer and i been researching round everywhere and its really getting to me no! can someone please help or poiunt me in the right direction!!! thanks a lot! 
Where appropriate assume a propagation velocity of 2x108 m/s
Take K=103 M=106 G=109
A hypothetical bus network has fixed frame lengths of 500 bytes and an Ethernet collision detection system. Calculate the cable length at 10Mb/s, 100Mb/s and 1Gb/s at which collision detection fails. If this protocol is now to standardise on the maximum of the above lengths for all three data rates what parameter in the original protocol needs to be varied and what are the new values? Discuss the validity of the cable lengths calculated for the three data rates.
Where appropriate assume a propagation velocity of 2x108 m/s
Take K=103 M=106 G=109
A hypothetical bus network has fixed frame lengths of 500 bytes and an Ethernet collision detection system. Calculate the cable length at 10Mb/s, 100Mb/s and 1Gb/s at which collision detection fails. If this protocol is now to standardise on the maximum of the above lengths for all three data rates what parameter in the original protocol needs to be varied and what are the new values? Discuss the validity of the cable lengths calculated for the three data rates.