Dears,, Kindly, I need full and unique answers to these questions: Q1)Give the t

Question

Dears,,

Kindly, I need full and unique answers to these questions:

Q1)Give the type and value of each result of the following Java expressions.

a) (5 / 2) * 2.0

b) (5/2.0) * 2

c) "1.3" + "5.2"

d) 1 + 7.0 + "2" + "x"

Q2) For the following mathematical expressions, write the corresponding Java expressions.

Q3)

Given the following declaration:

int i1 = 1;

int i2 = 2;

String S1 = "Hello";

String S2 = "HELLO";

double d1 = 1.0;

double d2 = 2;

For each of the following comparisons, specify:

1) Which are syntactically correct?

2) Which are syntactically incorrect?

3) Which are syntactically correct but logically questionable?

Only specify the answer on the following table; an example is given.

Comparisons

Syntactically correct

Syntactically incorrect

Syntactically correct, but logically questionable

i1 == i2

X

d1 == d2

s1 == "Hello"

s1 == s2

s1 == d1

i2-d2 == null

i1.equals(i2)

d1.equals(d2)

(s1-s2).equals(null)

i1-i2 == 0

s1.equals(s2)

Q4) Write program that takes the user age as input. Then the program will display whether the person is authorized to participate in vote or not. A person’s age who is authorized to vote should be 18 years or older.

Example output:

Enter your age: 18

You are authorized to vote.

Comparisons

Syntactically correct

Syntactically incorrect

Syntactically correct, but logically questionable

i1 == i2

X

d1 == d2

s1 == "Hello"

s1 == s2

s1 == d1

i2-d2 == null

i1.equals(i2)

d1.equals(d2)

(s1-s2).equals(null)

i1-i2 == 0

s1.equals(s2)

Explanation / Answer

If you have any doubts kindly you can comment. I'll reply as soon as possible.
Kindly rate the answer.All the best. :)
*********************************************************************
Q1)Give the type and value of each result of the following Java expressions.

a) (5 / 2) * 2.0
Value: 4.0
Explanation: (5/2) evaluates to 2 because both 5 and 2 are integers and,
(5/2)*2.0 evaluates to 4.0 since 2.0 is a double. int*double = double(2*2.0=4.0)

b) (5/2.0) * 2
Value: 5.0
Explanation: (5/2.0) evaluates to 2.5 because 5 is int and 2 is doubleand,
(5/2.0)*2 evaluates to 5.0 since 2.5 is double and 2 is int. double*int = double(2.5*2=5.0)

c) "1.3" + "5.2"
Value:1.35.2
Explanation: Here + acts as concatenation operator and concatenates 2 strings "1.3" and "5.2".

d) 1 + 7.0 + "2" + "x"
Value:8.02x
Explanation: First the sum of 1 and 7.0 is calculated which is 8.0, then it is concatenated with "2" which becomes 8.02 and then again concatenates with "x" and becomes 8.02x

*********************************************************************
Q2.

double squareroot = Math.sqrt((x*x)-y);

Math.sqrt method in java finds the squareroot of the expression.

*********************************************************************

*********************************************************************
Q3.

Comparisons

Syntactically correct

Syntactically incorrect

Syntactically correct, but logically questionable

i1 == i2

X

d1 == d2

X

s1 == "Hello"

X

s1 == s2

X

s1 == d1

X

i2-d2 == null

X

i1.equals(i2)

X

d1.equals(d2)

X

(s1-s2).equals(null)

X

i1-i2 == 0

X

s1.equals(s2)

X

*********************************************************************

*********************************************************************
Q4.
The code is pretty straight :)
Use Scanner to take input.
Chec if age>=18 or not and print the appropriate message.

Code:

import java.util.Scanner;
public class Test {

   public static void main(String[] args) {
       System.out.println("Enter your age: ");
       Scanner sc = new Scanner(System.in);
       int age=sc.nextInt();
       if(age>=18)
           System.out.println("You are authorized to vote.");
       else
           System.out.println("You are not authorized to vote.");
       sc.close();
   }
}

Sample outputs:

***********************************************************************

I hope this helps you.
If you find my answer helpful,
Kindly rate the answer.
All the best :)

Comparisons

Syntactically correct

Syntactically incorrect

Syntactically correct, but logically questionable

i1 == i2

X

d1 == d2

X

s1 == "Hello"

X

s1 == s2

X

s1 == d1

X

i2-d2 == null

X

i1.equals(i2)

X

d1.equals(d2)

X

(s1-s2).equals(null)

X

i1-i2 == 0

X

s1.equals(s2)

X

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