5. (總分 15 分) Is a customer's preference for a cell phone affected by the age of the customer? If so, advertising might need to target a particular age group. Suppose a random sample of 500 customers aged 16 and older was selected, and their recent purchased cell phones along with their age groups were recorded, as shown in the table below.
| Age Group | Apple | Sony | Asus | Other |
|---|---|---|---|---|
| 16-21 | 75 | 34 | 10 | 6 |
| 21-30 | 89 | 42 | 19 | 10 |
| 30-49 | 54 | 52 | 28 | 18 |
| 50+ | 21 | 25 | 7 | 10 |
【題組】(b) (5 分) Suppose you were a marketing expert, how would you advise Apple (hint: which age group you would target, or what further information they should collect for advanced analyses?)