The exercise seems to be about calculating probabilities for binomial distributions with normal approximations, based on the scenario of employed adults holding multiple jobs. Let me walk through the questions and offer clarification where needed:

1. Part 1:

   • The question asks if it's appropriate to use the normal approximation for a sample of 68 adults. The condition for using the normal approximation is that both $np$ and $n(1-p)$ should be at least 10.
   • Here, $n = 68$ and $p = 0.05$, giving $np = 68 \times 0.05 = 3.4$, which is less than 10. Therefore, the normal approximation is not appropriate.

2. Part 2:

   • A sample of 336 adults is drawn, and the probability of less than 6.5% holding multiple jobs is calculated. The correct answer is given as 0.8964, indicating the probability that fewer than 6.5% of the sample holds multiple jobs.

3. Part 3:

   • This asks for the probability that more than 6.5% of the 336 adults hold multiple jobs. The answer provided is 0.1036, representing the tail probability for values greater than 6.5%.

4. Part 4:

   • It focuses on the proportion of individuals in the sample holding multiple jobs being between 0.054 and 0.10. The result, 0.3669, indicates the probability of this range occurring.

5. Part 5:

   • The question asks whether it would be unusual if less than 2.5% of individuals held multiple jobs in a sample of 336. To determine this, we need to find the probability for this event. The term "unusual" typically refers to a probability less than 0.05.

I can help you calculate the missing probability for Part 5 if you provide additional context or want further clarification on any steps.

Would you like a detailed explanation of how these probabilities were calculated or assistance with Part 5? Here are some follow-up questions:

1. Would you like to see how to calculate the probability from the binomial distribution in Part 2?
2. Do you need help calculating the exact value for Part 5?
3. Would you like a refresher on using the normal approximation for binomial distributions?
4. Do you want to understand how the cutoff of 0.05 for “unusual” is determined?
5. Would you like to explore another probability topic related to this problem?

Tip: Always check whether conditions for normal approximation hold before applying it to a binomial distribution.