Move the points z_a and z_b along the horizontal axis to compute the probability P(z_a < z < z_b). What is the probability P(-1<Z<1)=_________ P(-2<Z<2)=__________ P(-3<Z<3)=__________ P(0<Z<5)=__________
Now try the following P(Z<-1)=__________ P(Z>1)=__________ P(Z<-2)__________ P(Z>2)=__________ Does the probability ever become a negative value?