24. The red flame during the operation of a bessemer converter indicates that the

air is burning out silicon and manganese
silicon and manganese has burned out and carbon has started oxidising
converter must be tilted to remove the contents of the converter
red flame does not occ
✅ The correct answer is option D.

29. Thermosetting plastics are those materials which

are formed into shape under heat and pressure and results in a permanently hard product
do not become hard with the application of heat and pressure and no chemical change occurs
are flexible and can withstand considerable wear under suitable conditions
are used as a friction
✅ The correct answer is option A.