Answer:
D
Step-by-step explanation:
Answer:
The correct type of sampling is stratified.
Step-by-step explanation:
(1) The sample mean stands at 1480 hours while the population standard deviation is 80 hours.(2) The null hypothesis posits that the average lifespan of fluorescent bulbs is 1500 hours.(3) The critical value is 1.645.(4) The test statistic is D, -1.58.(5) The conclusion is B, we reject H0.(6) Thus, the conclusion indicates A, there isn't sufficient evidence to substantiate the claim that the average lifespan of its fluorescent bulbs is 1500 hours.