P7.3 A unity feedback system has the loop transfer function

K L(s) = Ge(s)G(s) = (s+2)(s+4)(s+6) Find (a) the breakaway point on the real axis and the gain K for this point, (b) the gain and the roots when two roots lie on the imaginary axis, and (c) the roots when K = 10. (d) Sketch the root locus.