public abstract class Account {		//abstract class //perent class     protected int accountNumber;     protected Customer customerObj;     protected double balance;   	//constructor   	public Account(int saccountNumber, Customer scustomerObj,double sbalance){         accountNumber = saccountNumber;         customerObj = scustomerObj;         balance = sbalance;     }   	// abstract Function     public abstract boolean withdraw(double amount);  }     public class SavingsAccount extends Account { // child class     private double minimumBalance;   	// constructor     public SavingsAccount(int saccountNumber, Customer scustomerObj, double sbalance, double sminimumBalance) {         super(saccountNumber, scustomerObj, sbalance);         minimumBalance = sminimumBalance;     } 	// Implementation of abstract function in child class     public boolean withdraw(double amount) {         if (balance() > minimumBalance && balance() - amount > minimumBalance) {             super.setBalance(balance() - amount);             return true;         } else {             return false;         }     } }

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