ƚ  pQ B .   &@  & MathType-0 Times New Roman؟ww wf-2 `| 5y2  3y2 n 2y2 `4y2 `F 2 `$ande2 `p 2 `7 2 J4 2 nD1 2 `47 Symbol ؟ww wf-2 `P  2 ` & "Systemf !-