Question: who is the author when featuring is Leela, The Master, Kraals?
SQL: SELECT "Author" FROM "2-1620397-7" WHERE "Featuring" = 'Leela, The Master, Kraals';

Question: who is the author when the title is Destination: Nerva?
SQL: SELECT "Author" FROM "2-1620397-7" WHERE "Title" = 'Destination: Nerva';

Question: who is featuring when the title is Energy of the Daleks?
SQL: SELECT "Featuring" FROM "2-1620397-7" WHERE "Title" = 'Energy of the Daleks';

Question: what is the title when the featuring is Leela and series sorted is 4S/B?
SQL: SELECT "Title" FROM "2-1620397-7" WHERE "Featuring" = 'Leela' AND "Series Sorted" = '4S/B';