#"Since P,Q and R resistances are parallel,their equivalent is : "#
#1/M=1/2+1/3+1/6#
#1/M=(3+2+1)/6#
#1/M=6/6#
#1/M=1#
#M=1Omega#
#M("equivalent resistance of P,Q,R")#
#"Since The circuit current does not pass ,the resistance S does not affect the equivalent resistance."#
#"The equivalent resistance is 1"Omega#