Write a Java class named Problem$1.$ A full$-$time car salesman gets a flat salary of $$10,000$ and a commission on car sales. A part$-$time car salesman gets only commission on car sales. Currently, the commission on sales is $2\mathrm{.}5\%$ of the total car sales. In this class, add a main method to ask the user whether the employee is full$-$time or part$-$time. Also, ask for the total car sales he$/$she made that year. Then compute the annual gross pay for that employee and display it$.$Write a Java class named Problem$2.$ In this class, add a main method that asks the user to enter the amount of a purchase. Then compute the state and county sales tax. Assume the state sales tax is $5$ percent and the county sales tax is $2\mathrm{.}5$ percent. Display the amount of the purchase, the state sales tax, the county sales tax, the total sales tax, and the total of the sale $($which is the sum of the amount of purchase plus the total sales tax$).$Write a Java class named Problem$3.$ In this class, add a main method that asks the user for total amount of purchase and computes the tax $($assume the tax rate is $7\%).$ Also, ask the user if the product is being shipped to New York. If yes, add an additional shipping fee of $$9\mathrm{.}99$ to the final cost. Display the total cost.Write a Java class named Problem$4.$ In this class, add a main method that asks the user for a letter and checks whether the letter is a vowel or consonant.Write a Java class named Problem$5.$ In this class, add a main method to input five numbers and only display the even ones if there are any.Write a Java class named Problem$6.$ In this class, add a main method that prompts the user for three numbers then displays them the in descending order.Write a Java class named Problem$7.$n this class, add a main method that takes a year from user and print out whether that year is a leap year or not. $1.$ The year can be evenly divided by $4,2.$ If the year can be evenly divided by $100,$ it is NOT a leap year, unless the year is also evenly divisible by $400.$ Then it is a leap year.