MLD1 Mid-Term Exam Part1

1. To make variable "dat" equal to 5 which of the following lines of Java code should be used:

Int dat = 5;

String dat = 5;

System.print.out(dat);

Dat = dat + 5;

The correct answer is "int dat = 5;". This line of code declares a variable named "dat" of type integer and assigns it the value of 5. This will make the variable "dat" equal to 5. The other options are incorrect because they either assign a string value to the variable or attempt to print the value without declaring the variable first.

Explanation

The correct answer is "int dat = 5;". This line of code declares a variable named "dat" of type integer and assigns it the value of 5. This will make the variable "dat" equal to 5. The other options are incorrect because they either assign a string value to the variable or attempt to print the value without declaring the variable first.

2. To make a Java program print "Java",
which of the following lines of Java code should be used:

Print(Java);

Print"Java";

System.out.print "Java";

System.out.print("Java");

The correct answer is System.out.print("Java"). This is because System.out.print is a method in Java that is used to print the specified text to the console. In this case, "Java" is the text that we want to print. The correct syntax for calling this method is to use parentheses () to enclose the text that we want to print. Therefore, the correct line of code to make a Java program print "Java" is System.out.print("Java").

Explanation

The correct answer is System.out.print("Java"). This is because System.out.print is a method in Java that is used to print the specified text to the console. In this case, "Java" is the text that we want to print. The correct syntax for calling this method is to use parentheses () to enclose the text that we want to print. Therefore, the correct line of code to make a Java program print "Java" is System.out.print("Java").

3. A program "class SavProg2" should be saved as:

SavProg2

SavProg2.txt

SavProg2.java

Class SavProg2.java

The correct answer is "SavProg2.java" because in Java, the convention is to save a program file with the same name as the main class in the program. In this case, the main class is "SavProg2", so the file should be saved as "SavProg2.java".

Explanation

The correct answer is "SavProg2.java" because in Java, the convention is to save a program file with the same name as the main class in the program. In this case, the main class is "SavProg2", so the file should be saved as "SavProg2.java".

4. Which character usually ends up a Java program code?

@

}

&

#

The character "}" usually ends up a Java program code. This character is used to close a block of code, such as a class, method, or loop. It is important to have matching opening and closing braces to ensure the code is properly structured and executed. The other characters mentioned (@, &, #) do not typically signify the end of a Java program code.

Explanation

The character "}" usually ends up a Java program code. This character is used to close a block of code, such as a class, method, or loop. It is important to have matching opening and closing braces to ensure the code is properly structured and executed. The other characters mentioned (@, &, #) do not typically signify the end of a Java program code.

5. You cannot compile your Java program until you

Erase it

Run it

Save it

Memorize it

To compile a Java program, it needs to be saved first. Saving the program ensures that the changes made to the code are stored in a file on the computer's storage. Once the program is saved, it can be compiled using a Java compiler, which will translate the code into a format that can be executed by the computer. Therefore, saving the Java program is a necessary step before compiling it.

Explanation

To compile a Java program, it needs to be saved first. Saving the program ensures that the changes made to the code are stored in a file on the computer's storage. Once the program is saved, it can be compiled using a Java compiler, which will translate the code into a format that can be executed by the computer. Therefore, saving the Java program is a necessary step before compiling it.

6. A Java class code contains the following line:public class Diamond
what is the actual name of the program (class)?

Public static void class Diamond

Class Diamond

Diamond

The actual name of the program (class) is "Diamond". This is because in Java, the name of the class should match the name given after the "public class" statement. So, in this case, the name of the class is "Diamond".

Explanation

The actual name of the program (class) is "Diamond". This is because in Java, the name of the class should match the name given after the "public class" statement. So, in this case, the name of the class is "Diamond".

7. A computer keyboard is a:

The main part of a computer

Output device

Input device

Storage device

A computer keyboard is classified as an input device because it allows users to input data and commands into a computer system. It consists of various keys that can be pressed to type letters, numbers, and special characters. The input from the keyboard is then processed by the computer's operating system or software applications. Keyboards are essential for tasks such as typing documents, sending emails, playing games, and navigating through computer interfaces.

Explanation

A computer keyboard is classified as an input device because it allows users to input data and commands into a computer system. It consists of various keys that can be pressed to type letters, numbers, and special characters. The input from the keyboard is then processed by the computer's operating system or software applications. Keyboards are essential for tasks such as typing documents, sending emails, playing games, and navigating through computer interfaces.

8. The line of Java code below has the last character missed.

answer = number1 + 3

The missed character is:

@

/

&

;

The missing character in the given line of Java code is a semicolon (;). A semicolon is used to indicate the end of a statement in Java. In this code, the semicolon is missing after the expression "number1 + 3", which is a syntax error. Adding the semicolon at the end will correct the code.

Explanation

The missing character in the given line of Java code is a semicolon (;). A semicolon is used to indicate the end of a statement in Java. In this code, the semicolon is missing after the expression "number1 + 3", which is a syntax error. Adding the semicolon at the end will correct the code.

9. The text below is a fragment of a Java code.

public class CalcNum {
public static void main(String[] args) {
double circ = 0

This code should be saved as:

Public class CalcNum

CalcNum.java

Class CalcNum

Class CalcNum.java

The correct answer is "CalcNum.java" because the code is defining a public class called "CalcNum" and the convention in Java is to save a public class in a file with the same name as the class, followed by the ".java" extension.

Explanation

The correct answer is "CalcNum.java" because the code is defining a public class called "CalcNum" and the convention in Java is to save a public class in a file with the same name as the class, followed by the ".java" extension.

10. An integer is:

Any whole number (includes positive, negative, and zero)

A whole number or a decimal

A negative whole number

A fraction

The correct answer is any whole number (includes positive, negative, and zero). This is because an integer is defined as a number that does not have a fractional or decimal part. It can be positive, negative, or zero, but it must be a whole number.

Explanation

The correct answer is any whole number (includes positive, negative, and zero). This is because an integer is defined as a number that does not have a fractional or decimal part. It can be positive, negative, or zero, but it must be a whole number.

Mld1 Mid-term Exam Part1