KS

src/main/java/com/zipcoder/payment/PaymentPresenter.java

 package com.zipcoder.payment;
 
+import java.util.Arrays;
+
 public class PaymentPresenter {
 
     public String toString(Payment[] payments) {
-        return null;
+        Arrays.sort(payments);
+        StringBuilder sb = new StringBuilder();
+        for (Payment o: payments) {
+            o.getID();
+            o.getPayerName();
+
+            sb.append(o.getShortDescription()+"\n");
+        }
+        return sb.toString();
     }
+
+
 }

src/test/java/com/zipcoder/payment/PaymentPresenterTest.java

         Payment Paypal = new Paypal(4L, "Tia Mowry", "tia@mowry.com");
         Payment check = new Check(81L, "Tia Mowry", "11432543", "134344551");
 
-        payment[0] = Paypal;
-        payment[1] = check;
+        payments[0] = Paypal;
+        payments[1] = check;
 
         PaymentPresenter presenter = new PaymentPresenter();
         String expected = "Check Tia Mowry ***4551\nPaypal Tia Mowry tia@mowry.com\n";