ƚ` I  .  `&  & MathType-Times New Roman؟ww wf-2 `322 %522 n"92 2 `or 2 `j 2 `322 522 n92Symbol ؟ww wf-2 `+22 ` =22 `+22 `x=2Times New Roman؟ww wf-2 `&C22 `b F22 `x22 `^y2 & "Systemf !-