6. (15 points) Compute the maximum number of dichotomies, mH(N), for these learning models. (a) Positive or negative ray: H contains the functions which are +1 on (a,) (for some a ), and 1 elsewhere, together with those that are +1 on (,a) (for some a ), and 1 elsewhere. (b) Positive or negative interval: H contains the functions which are +1 on an interval [a,b] and 1 elsewhere or 1 on an interval [a,b] and +1 elsewhere. (c) Two concentric spheres in Rd:H contains the functions which are +1 for ax12++xd2b and 1 elsewhere