For (a)–(c), is it a null hypothesis, or an alternative hypothesis?

(a) In Canada, the proportion of adults who favor legalized gambling equals 0.50.

(b) The proportion of all Canadian college students who are regular smokers now is less than 0.20 (the value it was 10 years ago).

(c) The mean IQ of all students at Lake Wobegon High School is larger than 100.

(d) Introducing notation for a parameter, state the hypotheses in (a)–

(c) in terms of the parameter values.