Note: (3) is correct because an abstract class doesn't have to implement any or all of its interface's methods. (4) is correct because the method is correctly implemented ((7 > 4) is a boolean). (1) is incorrect because interfaces don't implement anything. (2) is incorrect because classes don't extend interfaces. (5) is incorrect because interface methods are implicitly public, so the methods being implemented must be public.

Note: (1), (2) and (6) are valid array declarations. Option (3) is not a correct array declaration. The compiler complains with: illegal start of type. The brackets are in the wrong place. The following would work: public int[ ] a Option (4) is not a correct array declaration. The compiler complains with: ']' expected. A closing bracket is expected in place of the 3. The following works: private int a [] Option (5) is not a correct array declaration. The compiler complains with 2 errors: ']' expected. A closing bracket is expected in place of the 3 and <identifier> expected A variable name is expected after a[ ] .

Note: Option A and B are wrong because they use the default access modifier and the access modifier for the class is public (remember, the default constructor has the same access modifier as the class). Option D is wrong. The void makes the compiler think that this is a method specification - in fact if it were a method specification the compiler would spit it out.

Note: default access is the "package oriented" access modifier. Option A and C are wrong because public and protected are less restrictive. Option B and D are wrong because abstract and synchronized are not access modifiers.

Note: All the given statements are legal declarations.

Note: Option B generates a compiler error: <identifier> expected. The compiler thinks you are trying to create two arrays because there are two array initialisers to the right of the equals, whereas your intention was to create one 3 x 3 two-dimensional array. To correct the problem and make option B compile you need to add an extra pair of curly brackets: int [ ] [ ] scores = { {2,7,6}, {9,3,45} };

Note: (2), (3), and (5). These are all valid interface method signatures. (1), is incorrect because an interface method must be public; if it is not explicitly declared public it will be made public implicitly. (4) is incorrect because interface methods cannot be static.

Note: The only two real contenders are C and D. Protected access Option C makes a member accessible only to classes in the same package or subclass of the class. While default access Option D makes a member accessible only to classes in the same package.

Note: However A, B and C are all wrong. Each of these would result in a narrowing conversion. Whereas we want a widening conversion, therefore the only correct answer is D. Don't be put off by the long cast, this applies only to the variable x and not the rest of the expression. It is the variable y (of type double) that forces the widening conversion to double. Java's widening conversions are: - From a byte to a short, an int, a long, a float, or a double. - From a short, an int, a long, a float, or a double. - From a char to an int, a long, a float, or a double. - From an int to a long, a float, or a double. - From a long to a float, or a double. - From a float to a double.

Note: Option A is correct - because the class that extends A is just simply overriding method1. Option B is wrong - because it can't override as there are less access privileges in the subclass method1. Option C is wrong - because to override it, the return type needs to be an integer. The different return type means that the method is not overriding but the same argument list means that the method is not overloading. Conflict - compile time error. Option D is wrong - because you can't override a method and make it a class method i.e. using static.