In an engineering component made of ASTM 30 Gray Cast Iron (use Shigley's tables), the critical element is subjected to the stress components σ x =9ksi,σ y =−15ksi,σ z =6ksi, τ xy =12ksi,τ yz =τ xz =0. Determine the safety factors based on (a) MNST, (b) CMT, and (c) MMT.