1.1.5 Intro to programming quiz review

Consider the following code segment in the image

• 1

• 0.0

• 1.0

• 8.0

• 0.0

Answer explanation

In the following statements, the values of variables a, b, and c are plugged into this expression: a b / c a / b c

int a = 5;

int b = 4;

int c = 2;

double x = a b / c a / b c;

The expression is evaluated using the precedence of operators, as follows:

a b / c a / b c

= 5 4 / 2 5 / 4 2 // 5 / 4 is 1, as it is integer division.

= 20 / 2 1 * 2 // 20 / 2 is 10, as

it is integer division.

= 10 2

= 8

8 is assigned to double type variable x, therefore the output is 8.0.

Answer the question in the image

• 10 11 45 25

• 10 11 46 25

• 10 11 47 26

• 10 10 46 25

• 10 10 40 20

Answer explanation

The execution of the statements is as follows:

int score = 10; // The value of 10 is assigned to the variable score.

System.out.print(score  + " ");

// The value of score, 10, is displayed and followed by a space.

System.out.print(score++  + " ");

/* The value of score, 10, is then incremented to 11. */

score *= 2;

// The value of score, 11, is doubled, making it 22.

System.out.print(++score*2  + " ");

/* The value of score is incremented to 23 first, so 46 is displayed.

*/ int penalty = 4;

// The value of 4 is assigned to penalty. score += penalty/2;

// The result of 4/2 = 2 is added to score, making it 25.

System.out.print(score  + " ");

// 25 is displayed.

So, the complete output is 10 10 46 25.

How many bytes are occupied by a variable of the int data type in the Java programming language?

• 1

• 2

• 4

• 8

• 16

Answer explanation

An int data type variable in Java occupies 4 bytes of memory.

• final float PI = 3.14;

  System.out.println("The volume of a cylinder is: " + (PI*radius*radius*height) );

• int PI = 3.14;

  System.out.println("The volume of a cylinder is: "+ (PI*radius*radius*height) );

• final double pi = 3.14;

  System.out.println("The volume of a cylinder is: "+ (PI*radius*radius*height) );

• final double PI = 3.14;

  System.out.println("The volume of a cylinder is: "+ (PI*radius*radius*height) );

• final double PI;

  System.out.println("The volume of a cylinder is: "+ (PI*radius*radius*height) );

Answer explanation

The value of pi is constant, so the desired output requires the usage of the final keyword for declaring a named constant.

Choice D declares a named constant PI with the appropriate data type and uses it to display the output as required.

Choice A is not correct, as the declaration statement is assigning a double value to a float type constant, which will generate a syntax error. Recall that floating type literals are of the double data type by default in Java.

Choice B does not declare a named constant.

Choice C will generate a syntax error, as the declaration statement declares the named constant as pi and uses PI in System.out.println().

Choice E will generate a syntax error, as the declaration statement does not assign a constant value.

Which of the following statements is true?

• Integer variables cannot be used as an operand for the / operator.

• The data type of a variable is used to determine where the variable is stored in computer memory when the program is executed.

• In Java, the data types in the declaration statements of named constants are needed only for documentation purposes.

• The data type of a variable determines the kind of operations that can be performed on the variable.

• Variables of the float data type are represented in memory as strings of decimal digits with a decimal point and an optional sign.

Answer the question in the image.

• Happy New YearWelcome 2022

• Happy New Year Welcome2022

• HappyNewYearWelcome2022

• Welcome 2022 Happy New Year

• Happy New Year Welcome 2022

Which of the following data types is the correct option for creating a variable that can be assigned the numeric value 345.67?

• double

• boolean

• int

• byte

• char

What will be the final answer to the following arithmetic expression if it is evaluated using rules of operator precedence and associativity?

y += u + v * w/x – z

where u = 5, v = 3, w= 4, x= 6, z = 2.

Assume all variables are of integer data type.

Answer explanation

y += u + v * w/x – z

where u = 5, v = 3, w= 4, x= 6, z = 2.

y += 5 + (3 * 4)/6 - 2

y += 5 + (12/6) -2

y += (5 + 2) - 2

y += (7 - 2)

y += 5

*Can't go any further, since we don't know the value of y