called upon to operate. Each relay also has a \( 0.01 \% \) chance of nuisance tripping. - Option 2: Provide a single numerical relay with three (3) \( 50 / 51 \) and one (1) \( 50 \mathrm{~N} / 51 \mathrm{~N} \) measuring elements in the single device. This relay has a \( 0.999 \% \) chance of operating correctly when called upon to operate. This relay also has a \( 0.005 \% \) chance of nuisance tripping. a) Using probability analysis, which option is more dependable? b) Using probability analysis, which option is more secure