8. . A Nielsen survey provided the estimate that the mean number of hours of television viewing per household is 7 .25 hours per day . assume that the Nielsen survey involved 200 households and that the sample standard deviation was 2.5 hours per day . Ten years ago the population mean number of hours of television viewing per household was repoed to be 6.70 hours . Letting a\" = the opulation mean number of hours of television viewing per household in , test tie hypotheses H : a\" i 6.70 and H :1\" 6.70. usea=0.01