? 2c5s? 2.1 G 2 2.2  ap R ?¤è÷  bp R ?¤1  c p êè ^?ê OC ê  d p  e ? ?  fp 2.4  a C=1 Y=AB C=0 Y=B  b C=1 Y=AB+AB C=0 Y=B 0  c C=0 Y=AB C=1 Y=A  d C=1 Y=AB C=0 Y=AB 2.5 R Lmin =0.553k$ R Lmax =2.308k$ R Lmin ? R L ? R Lmax 2.6 Y=AB+AB 2.7 F 1 =ABC F 2 = A+B+C F 3 =  A+B  C+D F 4 = AB+CD 2.8 F= AB?#$?%?&