Question 1[2 + 1 + 3 + 2 = 8] Two brands of refrigerators, denoted A and B, are each guaranteed for 1 year. In a random sample of 100 refrigerators of brand A, 10 were observed to fail before the guarantee period ended. An independent random sample of 150 brand B refrigerators also revealed 15 failures during the guarantee period. Test the claim that 5% more of Brand A than Brand B fail before the guarantee expires. Use a significance level of 1%. (Round off to three decimals)