Probability

The events
C : "The person can speak Cantonese" and
H : "The person is from Hong Kong"
are dependent events.
So P(C and H) does not equal P(C)P(H) but P(C and H) = P(H)P(C|H)
P(H) = 0.006
P(C) = 0.08
P(C|H) and P(H|C) are not given.
P(C|H) is the probability that a person can speak Cantonese if the person is from Hong Kong. By common sense nearly every person from Hong Kong can speak Cantonese so P(C|H) is very very close to 1.
A good estimate for P(C and H) is 0.006 x 1 = 0.006

From the question, it does not mention whether two event is independent or not, so it is better to assume that they are independent. Because people from HK may or may not speak Cantonese, and people can speak Cantonese may or may not from HK.
let the event
C: the person picked can speak Cantonese
H: the person picked is from Hong Kong
are independent event.

so the probability should be
P(C and H) = P(C) x P(H)
=0.006 x 0.08 = 0.00048

Probability=0.006x0.08=0.00048