Before I give you some pointers, I suspect that this homework was not set today. So, next time it might be an idea to ask a little earlier if you need help, as we can't guarantee to answer all questions quickly.
Having found nothing on Bangladesh history on the forum I googled 'Bangladesh 1998' which resulted in over 30 million hits. However, the first two I looked at were very useful.
This one from the Esex Grid for learning was a very useful introduction. The
next one was from a school Geography department and gave more detail. Hopefully this should give you all you need, but if not then keep trying the Google results.
Remember, teachers prefer one page in your own words to ten pages just copied and pasted.