Actually otba is easy if u have read the material once or twice as it makes it easy to find out the answer easily. but when u don't read and go it takes time to find the answer and as we know time matters a lot while the exam. So I suggest u tired and go in the exam as it is mostly preferable. I hope this helped you.
2 5 2
bcoz i am giving in first time .in which class u study in which school.
apne kabi o.t.b.a deya h kya easy,hard,medium kya h
I study in Delhi Public School Vadodara
I am in 10th Std and I have given otba and it was much easier than I expected
so no need to worry much about it and all the best for ur exams
Read it .
after completing see sample Q.
books also available Q. are given
otba are as like paragraphs in eng. 
in exam Q.will be  asked find form it and ans. them
1 5 1
class 9 mei bhi pehli bar de raha hun and i dont no about difficuty which school u study in place your school situated.
dav cuttack odisha
ok u live in orrisa.