well i m not a qualified one but to share my thought i may say:
1. quantity is not a mattr here, all matter is quality.
2. to justify 20 marks question, we have to answer atleast to b elligible to get those 20 marks...
3. good start which must attract the reader..
4. words ample of vocabulary will b needed for this puorpose..
if any mistake, i appologise..
May Allah bless we all..