5) A contracting company claims that the proportion of the indicator lights on the road that are still working after 5 years is at least 90%; if a previous test of 100 indicators showed that the proportion that is still working after 5 years is 83%, with a significance level of 5%. a) Find the value of the test statistic. b) What is the p-value? c) Should the contractor's claim of at least 90% working after 5 years be rejected