Product calculation
import java.text.DecimalFormat; // Product excluding tax class class ProductExcludingTax { private String productName; private int quantity; private double price; private double taxRate; // Tax rate as a decimal (e.g., 0.1 for 10% tax) // Constructor public ProductExcludingTax(String productName, int quantity, double price, double taxRate) { this.productName = productName; this.quantity = quantity; this.price = price; this.taxRate = taxRate; } // Calculate total amount including tax public double calculateTotalAmount() { double totalAmount = quantity * price; double taxAmount = totalAmount * taxRate; return totalAmount + taxAmount; } // ...