AP Computer Science A Easy practice

Which of the following correctly declares a boolean variable and assigns it the result of a comparison?

// Option A
boolean result = (7 > 3);

// Option B
Boolean result = 7 > 3;

// Option C
bool result = 7 > 3;

// Option D
boolean result = "7 > 3";

What is the output of the following code?

ArrayList<String> list = new ArrayList<>();
list.add("dog");
list.add("cat");
list.add("dog");
list.add("bird");
int count = 0;
for (String s : list) {
    if (s.equals("dog")) count++;
}
System.out.println(count);

What is the output of the following code?

String s = "Hello, World!";
System.out.println(s.length());

What is the output of the following code?

ArrayList<Integer> list = new ArrayList<>();
for (int i = 1; i <= 5; i++) {
    list.add(i);
}
for (int i = 0; i < list.size(); i++) {
    System.out.print(list.get(i) + " ");
}

Which boolean expression correctly checks whether x is between 1 and 10 (inclusive)?

What is the output of the following code?

String s = "Hello World";
System.out.println(s.substring(6));

What is the output of the following code?

int[] nums = {3, 1, 4, 1, 5};
int max = nums[0];
for (int n : nums) {
    if (n > max) {
        max = n;
    }
}
System.out.println(max);

What is the output of the following code?

int sum = 0;
for (int i = 1; i <= 5; i++) {
    sum += i;
}
System.out.println(sum);

What is the output of the following code?

boolean a = true;
boolean b = false;
System.out.println(!a || b);
System.out.println(!(a || b));

What is the output of the following code?

int x = 10;
x += 3;
x *= 2;
x -= 7;
System.out.println(x);

What is the value of count after the following code executes?

int count = 0;
for (int i = 0; i < 4; i++) {
    for (int j = 0; j < 3; j++) {
        count++;
    }
}

What is the output of the following code?

int i = 1;
while (i < 16) {
    i *= 2;
}
System.out.println(i);

What is the output of the following code?

int x = 1;
do {
    System.out.print(x + " ");
    x *= 3;
} while (x < 30);

What is the output of the following code?

int[][] m = {{2, 4}, {6, 8}};
for (int r = 0; r < m.length; r++) {
    for (int c = 0; c < m[r].length; c++) {
        System.out.print(m[r][c] + " ");
    }
}

Given the following classes:

public class Animal {
    public String speak() { return "..."; }
}
public class Dog extends Animal {
    public String speak() { return "Woof"; }
}

What does the following print?

Animal a = new Dog();
System.out.println(a.speak());