Commercial aircraft used for flying in instrument conditions are required to have two independent radios instead of one. Assume that for a typical flight, the probability of a radio failure is...

Commercial aircraft used for flying in instrument conditions are required to have two independent radios instead of one. Assume that for a typical flight, the probability of a radio failure is 0.0028. What is the probability that a particular flight will be safe with at least one working radio? Why does the usual rounding rule of three significant digits not work here? Is this probability high enough to ensure flight safety?

(Round to six decimal places as needed)