\magnification \magstep 1 \def\jmp{\medskip\noindent} \def\C{Cheng Problem~~} \def\hfb{\hfil\break\noindent} \nopagenumbers \jmp {\bf ENEE 380 Fall 1999. Homework \#4} \jmp {\bf Due November 22, 1999} \jmp \jmp (1) \C (4.15) \jmp (2) \C (4.16) \jmp (3) \C (4.17) \jmp (4) \C (4.21) \jmp (5) \C (4.23) \jmp (6) \C (4.25) \jmp (7) \C (4.27) \jmp (8) \C (5.3) \jmp (9) \C (5.6) \jmp (10) \C (5.8) \vfill\eject\end