a In Check Your Progress 2 the circle relation C was defined as follows For any (x,y) E Rx R. (x,y) E C means that x² + y² = 4 Is C a function? If it is, find C(O) and C(2) b. Define a relation from R to R as follows: For all (x, y) E Rx R, (1. y) € M means that x² + y = Is Ma function? If it is, find M(-1) and (0) ​