added comments

app/src/main/java/com/elearning/probabilityandstatisticsanalyserandeducator/calculationfunction/StandaradDeviationCalculation.java

@@ -26,6 +26,7 @@ public class StandaradDeviationCalculation extends AppCompatActivity {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_standarad_deviation_calculation);
 
+        //object creation
         FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
 
         Bundle bundle = new Bundle();
@@ -33,7 +34,7 @@ public class StandaradDeviationCalculation extends AppCompatActivity {
         Intent intent = getIntent();
         array = intent.getStringArrayExtra("dataset");
 
-//create DestatCalculation object
+//create StdCalculation object
         StdCalculation stdCalculation = new StdCalculation();
 
         ArrayList<Object> populationstdlist = new ArrayList<Object>();