Java Unit 2 #2

____________ is the Java assignment operator. A. == B. := C. = D. =:

C

Which of the following are correct names for variables according to Java naming conventions? A. radius B. Radius C. RADIUS D. findArea E. FindArea

A,D

Which of the following statements are the same? (A) x -= x + 4 (B) x = x + 4 - x (C) x = x - (x + 4) A. (A) and (B) are the same B. (A) and (C) are the same C. (B) and (C) are the same D. (A), (B), and (C) are the same

B

According to Java naming convention, which of the following names can be variables? A. FindArea B. findArea C. totalLength D. TOTAL_LENGTH E. class

B,C

Math.pow(2, 3) returns __________. A. 9 B. 8 C. 9.0 D. 8.0

D

To assign a double variable d to a float variable x, you write A. x = (long)d B. x = (int)d; C. x = d; D. x = (float)d;

D

To obtain the current hour in UTC, use _________. A. System.currentTimeMillis() % 3600 B. System.currentTimeMillis() % 60 C. System.currentTimeMillis() / 1000 % 60 D. System.currentTimeMillis() / 1000 / 60 % 60 E. System.currentTimeMillis() / 1000 / 60 / 60 % 24

E

Are the following four statements equivalent? number += 1; number = number + 1; number++; ++number; A. Yes B. No

A

Every letter in a Java keyword is in lowercase? A. true B. false

A

The expression (int)(76.0252175 * 100) / 100 evaluates to _________. A. 76.02 B. 76 C. 76.0252175 D. 76.03

B

What is the result of 45 / 4? A. 10 B. 11 C. 11.25 D. 12

B

What is the value of (double)5/2? A. 2 B. 2.5 C. 3 D. 2.0 E. 3.0

B

What is x after the following statements? int x = 1; x *= x + 1; A. x is 1. B. x is 2. C. x is 3. D. x is 4

B

What is y displayed? public class Test { public static void main(String[] args) { int x = 1; int y = x + x++; System.out.println("y is " + y); } } A. y is 1. B. y is 2. C. y is 3. D. y is 4.

B

The __________ method returns a raised to the power of b. A. Math.power(a, b) B. Math.exponent(a, b) C. Math.pow(a, b) D. Math.pow(b, a)

C

To declare an int variable number with initial value 2, you write A. int number = 2L; B. int number = 2l; C. int number = 2; D. int number = 2.0;

C

Which of the following assignment statements is incorrect? A. i = j = k = 1; B. i = 1; j = 1; k = 1; C. i = 1 = j = 1 = k = 1; D. i == j == k == 1;

C,D

If you attempt to add an int, a byte, a long, and a double, the result will be a __________ value. A. byte B. int C. long D. double

D

Which of the following assignment statements is illegal? A. float f = -34; B. int t = 23; C. short s = 10; D. int t = (int)false; E. int t = 4.5;

D,E

-25 % 5 is _____ A. 1 B. 2 C. 3 D. 4 E. 0

E

25 % 1 is _____ A. 1 B. 2 C. 3 D. 4 E. 0

E

Which of the following is a constant, according to Java naming conventions? A. MAX_VALUE B. Test C. read D. ReadInt E. COUNT

A,E

To improve readability and maintainability, you should declare _________ instead of using literal values such as 3.14159. A. variables B. methods C. constants D. classes

C

Which of the following is incorrect? A. int x = 9; B. long x = 9; C. float x = 1.0; D. double x = 1.0;

C

If a number is too large to be stored in a variable of the float type, it _____________. A. causes overflow B. causes underflow C. causes no error D. cannot happen in Java

A

Suppose a Scanner object is created as follows: Scanner input = new Scanner(System.in); What method do you use to read an int value? A. input.nextInt(); B. input.nextInteger(); C. input.int(); D. input.integer();

A

Suppose x is 1. What is x after x -= 1? A. 0 B. 1 C. 2 D. -1 E. -2

A

What is i printed in the following code? public class Test { public static void main(String[] args) { int j = 0; int i = j++ + j * 5; System.out.println("What is i? " + i); } } A. 0 B. 1 C. 5 D. 6

A

Which of the following are correct ways to declare variables? A. int length; int width; B. int length, width; C. int length; width; D. int length, int width;

A,B

Which of the following are the same as 1545.534? A. 1.545534e+3 B. 0.1545534e+4 C. 1545534.0e-3 D. 154553.4e-2

A,B,C,D

_____________ seeks to analyze the data flow and to identify the system?s input and output. When you do analysis, it helps to identify what the output is first, and then figure out what input data you need in order to produce the output. A. Requirements specification B. Analysis C. Design D. Implementation E. Testing

B

What is x after the following statements? int x = 2; int y = 1; x *= y + 1; A. x is 1. B. x is 2. C. x is 3. D. x is 4.

D

Which of the following expression results in a value 1? A. 2 % 1 B. 15 % 4 C. 25 % 5 D. 37 % 6

D

Math.pow(4, 1.0 / 2) returns __________. A. 2 B. 2.0 C. 0 D. 1.0 E. 1

B

Which of these data types requires the most amount of memory? A. long B. int C. short D. byte

A

_____________ is a formal process that seeks to understand the problem and document in detail what the software system needs to do. A. Requirements specification B. Analysis C. Design D. Implementation E. Testing

A

Which of the following is a valid identifier? A. $343 B. class C. 9X D. 8+9 E. radius

A,E

To add a value 1 to variable x, you write A. 1 + x = x; B. x += 1; C. x := 1; D. x = x + 1; E. x = 1 + x;

B,D,E

Which of the following expressions will yield 0.5? A. 1 / 2 B. 1.0 / 2 C. (double) (1 / 2) D. (double) 1 / 2 E. 1 / 2.0

B,D,E

Analyze the following code: public class Test { public static void main(String[] args) { int n = 10000 * 10000 * 10000; System.out.println("n is " + n); } } A. The program displays n is 1000000000000. B. The result of 10000 * 10000 * 10000 is too large to be stored in an int variable n. This causes an overflow and the program is aborted. C. The result of 10000 * 10000 * 10000 is too large to be stored in an int variable n. This causes an overflow and the program continues to execute because Java does not report errors on overflow. D. The result of 10000 * 10000 * 10000 is too large to be stored in an int variable n. This causes an underflow and the program is aborted. E. The result of 10000 * 10000 * 10000 is too large to be stored in an int variable n. This causes an underflow and the program continues to execute because Java does not report errors on underflow.

C

To obtain the current second, use _________. A. System.currentTimeMillis() % 3600 B. System.currentTimeMillis() % 60 C. System.currentTimeMillis() / 1000 % 60 D. System.currentTimeMillis() / 1000 / 60 % 60 E. System.currentTimeMillis() / 1000 / 60 / 60 % 24

C

What is the exact output of the following code? double area = 3.5; System.out.print("area"); System.out.print(area); A. 3.53.5 B. 3.5 3.5 C. area3.5 D. area 3.5

C

What is y displayed in the following code? public class Test { public static void main(String[] args) { int x = 1; int y = x++ + x; System.out.println("y is " + y); } } A. y is 1. B. y is 2. C. y is 3. D. y is 4.

C

_______ is the code with natural language mixed with Java code. A. Java program B. A Java statement C. Pseudocode D. A flowchart diagram

C

-24 % -5 is _____ A. 3 B. -3 C. 4 D. -4 E. 0

D

-24 % 5 is _____ A. -1 B. -2 C. -3 D. -4 E. 0

D

24 % 5 is _____ A. 1 B. 2 C. 3 D. 4 E. 0

D

Analyze the following code. public class Test { public static void main(String[] args) { int month = 09; System.out.println("month is " + month); } } A. The program displays month is 09. B. The program displays month is 9. C. The program displays month is 9.0. D. The program has a syntax error, because 09 is an incorrect literal value.

D

Math.pow(4, 1 / 2) returns __________. A. 2 B. 2.0 C. 0 D. 1.0 E. 1

D

Suppose x is 1. What is x after x += 2? A. 0 B. 1 C. 2 D. 3 E. 4

D

To declare a constant MAX_LENGTH inside a method with value 99.98, you write A. final MAX_LENGTH = 99.98; B. final float MAX_LENGTH = 99.98; C. double MAX_LENGTH = 99.98; D. final double MAX_LENGTH = 99.98;

D

To obtain the current minute, use _________. A. System.currentTimeMillis() % 3600 B. System.currentTimeMillis() % 60 C. System.currentTimeMillis() / 1000 % 60 D. System.currentTimeMillis() / 1000 / 60 % 60 E. System.currentTimeMillis() / 1000 / 60 / 60 % 24

D

What is i printed? public class Test { public static void main(String[] args) { int j = 0; int i = ++j + j * 5; System.out.println("What is i? " + i); } } A. 0 B. 1 C. 5 D. 6

D

What is the output of the following code: double x = 5.5; int y = (int)x; System.out.println("x is " + x + " and y is " + y); A. x is 5 and y is 6 B. x is 6.0 and y is 6.0 C. x is 6 and y is 6 D. x is 5.5 and y is 5 E. x is 5.5 and y is 5.0

D

To add number to sum, you write (Note: Java is case-sensitive) A. number += sum; B. number = sum + number; C. sum = Number + sum; D. sum += number; E. sum = sum + number;

D,E

The System.currentTimeMillis() returns ________________ . A. the current time. B. the current time in milliseconds. C. the current time in milliseconds since midnight. D. the current time in milliseconds since midnight, January 1, 1970. E. the current time in milliseconds since midnight, January 1, 1970 GMT (the Unix time).

E

To assign a value 1 to variable x, you write A. 1 = x; B. x = 1; C. x := 1; D. 1 := x; E. x == 1;

B

Which of the following expression results in 45.37? A. (int)(45.378 * 100) / 100 B. (int)(45.378 * 100) / 100.0 C. (int)(45.378 * 100 / 100) D. (int)(45.378) * 100 / 100.0

B

What is the value of (double)(5/2)? A. 2 B. 2.5 C. 3 D. 2.0 E. 3.0

D

The following code fragment reads in two numbers: Scanner input = new Scanner(System.in); int i = input.nextInt(); double d = input.nextDouble(); What are the correct ways to enter these two numbers? A. Enter an integer, a space, a double value, and then the Enter key. B. Enter an integer, two spaces, a double value, and then the Enter key. C. Enter an integer, an Enter key, a double value, and then the Enter key. D. Enter a numeric value with a decimal point, a space, an integer, and then the Enter key.

A,B,C

If you enter 1 2 3, when you run this program, what will be the output? import java.util.Scanner; public class Test1 { public static void main(String[] args) { Scanner input = new Scanner(System.in); System.out.print("Enter three numbers: "); double number1 = input.nextDouble(); double number2 = input.nextDouble(); double number3 = input.nextDouble(); // Compute average double average = (number1 + number2 + number3) / 3; // Display result System.out.println(average); } } A. 1.0 B. 2.0 C. 3.0 D. 4.0

B

The expression 4 + 20 / (3 - 1) * 2 is evaluated to A. 4 B. 20 C. 24 D. 9 E. 25

C