Answer :
Keep in mind the definition of a function. For 2 points, (x,y) and (x,z) it is a function only if y = z.
Because you have the points {0.3,0.6} and {0.3,0.7}, for it to be a function, 0.6 would have to equal 0.7. Since this is clearly false, it is not a function.
Because you have the points {0.3,0.6} and {0.3,0.7}, for it to be a function, 0.6 would have to equal 0.7. Since this is clearly false, it is not a function.