Using article 37 (the Spherical Law of Cosines) determine a formula for finding the shortest distance between two points on a sphere with radius r (the distance along a great circle).

3) Which of the following are acceptable assignments of probabilities to the simple events of S = {a,b,c,d}. Give reason for each. 3 4 A) P(a) = P(b) = P(c) = 0, P(d) = 8' 5 B) P(a) = , P(b)= -5, P(c)=0, P(d)=1 C) P(a) = 0.2, P(b)=0, P(c)=0.4, P(d)=0.6

Can anyone please help me to solve this problem? I am stuck!