I keep getting these questions wrong, we can use R studio but i dont know which codes to use them if they are use

3. Suppose the time a child spends waiting at for the bus as a school bus stop is exponentially distributed with mean 6 minutes. Determine the probability that the child must wait at least 7 minutes on the bus on a given morning. a) 0.6114 b) 0.3114. c) 0.6228 d) 0.5114 e) 0.1886

4. Costs for standard veterinary services at a local animal hospital follow a Normal distribution with a mean of $77 and a standard deviation of $22. What is the probability that one bill for veterinary services costs less than $103? a) 0.5593 b) 0.4407 c) 0.8814 d) 0.5000 e) 0.1186

5. Suppose that x is normally distributed with a mean of 50 and a standard deviation of 10. What is P(x 74.50)? a) 0.493 b) 0.995 c) 0.007 d) 0.993 e) 0.496

6. Find a value of c so that P(Z c) = 0.74. a) 1.14 b) 1.64 c) 0.36 d) 0.64 e) 0.64 7. A random sample of 1444 14-ounce cans of fruit nectar is drawn from among all cans produced in a run. Prior experience has shown that the distribution of the contents has a mean of 14 ounces and a standard deviation of .14 ounce. What is the probability that the mean contents of the 1444 sample cans is less than 13.993 ounces?

a) 0.029 b) 0.049 c) 0.069 d) 0.059 e) 0.039

8. In a large population, 81% of the households have cable tv. A simple random sample of 196 households is to be contacted and the sample proportion computed. What is the mean and standard deviation of the sampling distribution of the sample proportions?

a) mean = 0.81, standard deviation = 0.2680

b) mean = 0.81, standard deviation = 0.0280

c) mean = 0.81, standard deviation = 0.0008

d) mean = 158.76, standard deviation = 0.0008

e) mean = 158.76, standard deviation = 0.0280