My friend rama owns a company. He claims that his batteries last at least 7.5 years on average. Your experience with rama's batteries have been somewhat different, so you decided to conduct a test to see if the claim us true. You collected a sample of 25 rama's batteries and get the average life(in years) of 7.3 years and a standard deviation 1.2 years. What is our conclusion at the 5% level of significance? P-value?