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Ans.  a.  Syntax error
              b. This loop is an infinite loop.
              c. while( x <=5 )
           8.  What are String Class Methods in Java? Consider the statement               [CBSE Sample Paper 2023]
             String name = ‘‘Hello World’’.
              Write a single line Java code using String methods to perform the following :
              (a) Convert the name to lowercase.
              (b) Replace “Hello” by “Welcome” in the given string.
              (c) Check whether the name contains ‘‘Sin’’ in it or not

              (d) Add a new string ‘‘jackpot” at the end of original string.
         Ans.  (a) name.toLowerCase( )
              (b) name.replace(”Hello”,“Welcome”)
              (c) name.contains(”Sin”)
              (d) name.concat(”jackpot”)
           9.  Write a code in java using a for loop to display all odd numbers between 1 to 10. Is for loop an entry controlled loop or exit
             control loop?                                                                 [CBSE Sample Paper 2023]

         Ans.  for (int count = 1; count <= 10; count = count +2)
             {System.out.println(count);}
             Entry control loop
          10.  What is the need of a constructor in OOP? Explain all features of a constructor.   [CBSE Sample Paper 2023]
         Ans.  A special method member called the constructor method is used to initialize the data members of the class.
              Features
              The constructor has the same name as the class, has no return type, and may or may not have a parameter list. Whenever
             a new object of a class is created, the constructor of the class is invoked automatically. We do not call the constructor
             explicitly.
          11.  Write the Mysql commands for the following queries:                         [CBSE Sample Paper 2023]
                TRAIN
                      TrainID           Station
                      0001        DELHI
                      0002        MUMBAI
               COUNTER

                    TicketID         Date           Cost          TrainNo
                      T1           12/3/22           500            0001
                      T2           15/5/22           450            0002
                      T3           15/5/22           500            0001
                (a) To find all the stations, date for ticket id as T1.
                (b) To find the total ticket amount collected from each station.
                (c) To displays all the tables created in the current database.
                (d) To delete table counter along with the information in it.
         Ans.  (a)  SELECT , DATE FROM TRAIN, COUNTER WHERE TRAIN.TrainID=COUNTER.TrainNO and TicketID=”T1”;
              (b)  SELECT SUM(COST), STATION FROM TRAIN, COUNTER WHERE TRAIN.TrainID=COUNTER.TrainNO GROUP BY STATION;
              (c)  SHOW TABLES;
              (d)  DROP TABLE COUNTER;





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