18. More De Morgan

Answer:
Using the De Morgan Rule
    !(A && B) is equivalent to !A || !B
The expression
    boolean discount =  !( (days < 14) && onSeason );
is equivalent to
    boolean discount =  !(days < 14) || !onSeason ; 
which can be further transformed to
    boolean discount =  days >= 14  || !onSeason ;

More De Morgan

De Morgan's rules can be extended to three operands:

!(A && B && C) is equivalent to !A || !B || !C
!(A || B || C) is equivalent to !A && !B && !C

Expressions with more than three operands behave similarly.


Question 18:
A driver holding a learner's permit may drive a car only during daylight hours and 
 only if accompanied by a licensed driver of age 21 or over.
    boolean drivingOK = daylight && passenger.age >= 21  && passenger.licensed;
Assume that passenger refers to an object with an integer member age
         and a boolean member licensed.
Here is an expression that says when driving is not permitted:
    boolean noDriving = !(daylight && passenger.age >= 21  && passenger.licensed );
Transform this into a simpler expression.