adding missing code for water sensor on week11 page

public/assignments/week11.html

@@ -234,7 +234,36 @@
 
                       <pre>
                         <code>
-                             
+                          /*
+                         * Created by ArduinoGetStarted.com
+                         *
+                         * This example code is in the public domain
+                         *
+                         * Tutorial page: https://arduinogetstarted.com/tutorials/arduino-water-sensor
+                         */
+
+                        #define POWER_PIN  14
+                        #define SIGNAL_PIN A0
+
+                        int value = 0; // variable to store the sensor value
+
+                        void setup() {
+                          Serial.begin(9600);
+                          pinMode(POWER_PIN, OUTPUT);   // configure D7 pin as an OUTPUT
+                          digitalWrite(POWER_PIN, LOW); // turn the sensor OFF
+                        }
+
+                        void loop() {
+                          digitalWrite(POWER_PIN, HIGH);  // turn the sensor ON
+                          delay(10);                      // wait 10 milliseconds
+                          value = analogRead(SIGNAL_PIN); // read the analog value from sensor
+                          digitalWrite(POWER_PIN, LOW);   // turn the sensor OFF
+
+                          Serial.print("Sensor value: ");
+                          Serial.println(value);
+
+                          delay(1000);
+                        }  
                         </code>
                       </pre>