1. Create a sequential file "std.dat" to store name and marks obtained in English, Math and Science subjects for a few students. (74 set 1) OPEN “std.dat” FOR OUTPUT AS #1 DO CLS INPUT “Enter name “; N$ INPUT “Enter English marks”; E INPUT “Enter Math's marks"; M INPUT "Enter Science marks"; S WRITE #1, N$, E, M, S INPUT "Do you want to continue (Y/N)";CH$ LOOP WHILE UCASE$ (CH$) "Y" CLOSE #1 END 4. WAP to add some more records in a data file “ABC.DAT” having following fields : patient’s name, address and age. OPEN “ABC.DAT” FOR OUTPUT AS #1 DO CLS INPUT “Enter Patients name “; N$ INPUT “Enter patients address”; A$ INPUT “Enter Patient's age "; A WRITE #1, N$, A$, A INPUT "Do you want to continue (Y/N)";CH$ LOOP WHILE CH$="Y" OR CH$="y" CLOSE #1 END 6.WAP to store records regarding the information of book’s number, name and author’s ...