A1: machine A and defective: 0.20*0.01 = 0.0020
A2: machine A and not defective: 0.20*0.99 = 0.1980
B1: machine B and defective: 0.30*0.02 = 0.0060
B2: machine B and not defective: 0.30*0.98 = 0.2940
C1: machine C and defective: 0.50*0.06 = 0.0300
C2: machine C and not defective: 0.50*0.94 = 0.4700
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1.0000