c.     False

                d.     False

1.4           H0: The 5 year survival rate for those using the vaccine is equal to 10%

                H1: The 5 year survival rate for those using the vaccine is greater than 10%

1.6          a. Since a Type I error is rejecting H0 when H0 is true, we would be concluding the electricity is no turned on when it is. Since a Type II error is accepting H0 when H1 is true, we would be thinking the electricity is turned on when it is not. A Type I error may be more serious as one might accidentally be electrocuted.

b. Since a Type I error is rejecting H0 when H0 is true, we would be concluding the brakes are operational when they are not. Since a Type II error is accepting H0 when H1 is true, we would be thinking the brakes are not operational when they are operational. A Type I error may be more serious as it may result in an accident.

c. Since a Type I error is rejecting H0 when H0 is true, we would be concluding the snake is not poisonous when it is poisonous. Since a Type II error is accepting H0 when H1 is true, we would be thinking the snake is poisonous when it is not poisonous. A Type I error may be more serious as it may result in getting bit by a poisonous snake. 

d. Since a Type I error is rejecting H0 when H0 is true, we would be concluding it is not safe to cross the street when it is safe. Since a Type II error is accepting H0 when H1 is true, we would be thinking it is safe to cross the street when it is not sate. A Type II error may be more serious as it may result in an accident.

1.8           a. Type I error: to classify a person as a drug user when he/she is not. Type II error: to classify a person as a non drug user when he/she actually is.

                b. Since the test classifies the person as a drug user (i.e. rejects H0) 4% of the time when the person is no a drug user (i.e. H0 is true), the chance of a Type I error is 4%.

1.20         The 0.05 indicates: (b) if H0 is true, the chance of falsely rejecting it is 0.05.