下列各种java类的定义，那种是错误的 A: class Animal{}class Dog extends Animal {} B: final class Animal{}class Dog extends Animal{} C: abstract class Animal{}class Dog extends Animal{} D: public class Animal{}class Dog extends Animal{}

Which animal is not the animal in Chinese Zodiac?

若Animal是Cat,Dog的父类，则下列选项中，正确的是（） A: Animal animal = new Cat(); B: Cat cat = (Cat)new Animal(); C: Animal animal = new Dog(); D: Cat cat = (Cat)new Dog();

若Animal是Cat,Dog的父类，则下列选项中，正确的是（） A: Animal animal = new Cat(); B: Animal a = new Cat(); Cat cat = (Cat) a; C: Animal animal = new Dog(); D: Cat cat = (Cat)new Dog();

The muscles of a fossilized animal can sometimes be reconstructed because______. A: they were preserved with the rest of the animal B: they were lodged inside the animal's skull C: they were hardened parts of the animal's body D: they were attached to the animal's skeleton

class Animal { public Animal() { System.out.println("Animal!"); } } public class Dog extends Animal{ public Dog() { System.out.println("Dog!"); } public static void main(String[] args) { Dog dog=new Dog(); } }

Many animal advocates oppose animal experimentation (vivisection) on ethical 4) ___

（7-1）定义了Animal类、Cat类和Dog类，则代码段是正确的。 class Animal{ }; class Cat extends Animal{} class Dog extends Animal{}

Animal 是抽象类 ，Dog类和Cat类继承了Animal 。Animal dog = new Dog（）；的写法是否正确？

It can be inferred from the passage that all of the following are with of producing new strains of influenza viruses except ______ . A: two influenza viruses in the same animal recombining B: animal viruses recombining with human viruses C: two animal viruses recombining in one animal D: two animal viruses recombining in a human