Which of these describes the system of linear equations below? 
3x-2y=7 
6x-4y=14 
a) the system has no solutions. 
b) the system has infinitely many solutions. 
c) the ration of the-coordinate to the y-coordinate of the only solution is 2 : 1. 
d) the difference between the x-coordinate and y-coordinate of the only solution is one.