Design a circuit that adds four 10-bit unsigned binary values and outputs an unsigned binary 10-bit result. The circuit also has a VALID output that indicates when the 10-bit unsigned binary result is valid. Note that when you add two 10-bit numbers, you will generate an 11-bit result (in some cases). Show the top two levels for this solution, meaning a top-level BBD, and the next lower level, which is RCAs and some gates. There is no need to show the next lower level, which would be the gate-level view of the RCAs. State how the circuit is controlled.

File account.java (see previous exercise) contains a definition for a simple bank account class with methods to withdraw, deposit, get the balance and account number, and return a string representation. note that the constructor for this class creates a random account number. save this class to your directory and study it to see how it works. then write the following additional code: 1. suppose the bank wants to keep track of how many accounts exist. a. declare a private static integer variable numaccounts to hold this value. like all instance and static variables, it will be initialized (to 0, since it’s an int) automatically. b. add code to the constructor to increment this variable every time an account is created. c. add a static method getnumaccounts that returns the total number of accounts. think about why this method should be static - its information is not related to any particular account. d. file testaccounts1.java contains a simple program that creates the specified number of bank accounts then uses the getnumaccounts method to find how many accounts were created. save it to your directory, then use it to test your modified account class.