Alright, so the distance formula is sqrt((x1-x2)^2+(y1-y2)^2), and plugging that in, we get sqrt((0-3)^2+(3-10)^2)=sqrt((-3)^2+(-7)^2)=sqrt(9+49)=sqrt(58)=around 7.6
Since we are given that it is an even number, we know there is only 3 options (2, 4, 6). Since only one of them is an even number, we know that we need the fraction 1/3 or 33.3% for a probability.