It looks like the second image you uploaded is the same as the first one. I’ve already solved both parts of the first question and also provided the solution for finding the value of $k$ in the second problem.

Would you like further clarifications, or do you have any other specific questions about these problems? Here are some additional questions that might deepen your understanding:

1. How can the concept of Z-scores be extended to other types of distributions?
2. What assumptions are made about the nature of the random variable in normal distribution problems?
3. Can you explain why the integral of a probability density function must equal 1?
4. How do transformations affect the mean and standard deviation of a normally distributed variable?
5. What role does the exponential distribution play in reliability and life data analysis?

Tip: When working with continuous probability distributions, always ensure that the total area under the curve equals 1, as it represents the total probability.