Ex.1
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(Convert Celsius to Fahrenheit) Write a program that reads a Celsius degree in
a double value from the console, then converts it to Fahrenheit and displays the
result. The formula for the conversion is as follows:
fahrenheit = (9 / 5) * celsius + 32
Hint: In Java, 9 / 5 is 1 , but 9.0 / 5 is 1.8 .

Here is a sample run:

Enter a degree in Celsius: 43
43 Celsius is 109.4 Fahrenheit

Ex. 2
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(Financial application: calculate tips) Write a program that reads the subtotal
and the gratuity rate, then computes the gratuity and total. For example, if the
user enters 10 for subtotal and 15% for gratuity rate, the program displays $1.5
as gratuity and $11.5 as total. 

Here is a sample run:
Enter the subtotal and a gratuity rate: 10 15
The gratuity is $1.5 and total is $11.5

Ex. 3
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(Sum the digits in an integer) Write a program that reads an integer between 0 and
1000 and adds all the digits in the integer. For example, if an integer is 932 , the
sum of all its digits is 14 .
Hint: Use the % operator to extract digits, and use the / operator to remove the
extracted digit. For instance, 932 % 10 = 2 and 932 / 10 = 93 .

Here is a sample run:
Enter a number between 0 and 1000: 999
The sum of the digits is 27

Ex. 4
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(Cost of driving) Write a program that prompts the user to enter the distance to
drive, the fuel efficiency of the car in miles per gallon, and the price per gallon,
and displays the cost of the trip. 

Here is a sample run:
Enter the driving distance: 900.5
Enter miles per gallon: 25.5
Enter price per gallon: 3.55
The cost of driving is $125.36

Ex. 5
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(Process a string) Write a program that prompts the user to enter a string and dis-
plays its length and its first character.

Ex. 6
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(Financial application: payroll) Write a program that reads the following infor-
mation and prints a payroll statement:
 Employee’s name (e.g., Smith)
 Number of hours worked in a week (e.g., 10)
 Hourly pay rate (e.g., 9.75)
 Federal tax withholding rate (e.g., 20%)
 State tax withholding rate (e.g., 9%)

A sample run is shown below:

Enter employee's name: Smith
Enter number of hours worked in a week: 10
Enter hourly pay rate: 9.75
Enter federal tax withholding rate: 0.20
Enter state tax withholding rate: 0.09
Employee Name: Smith
Hours Worked: 10.0
Pay Rate: $9.75
Gross Pay: $97.5
Deductions:
Federal Withholding (20.0%): $19.5
State Withholding (9.0%): $8.77
Total Deduction: $28.27
Net Pay: $69.2