When bs (i + b + h)cP0, it can be observed that the optimal
value of t2 does not always equal to zero from Fig. 2a and b. On
Fig. 2a, the optimal value of t2 does not occur at the point zero following
Theorem 1(a). On Fig. 2b, the optimal value of t2 only occurs
at the point zero following Theorem 1(c).