Exams

18 tens 20 ones, the given stateent can be split into

18 tens = 18 x 10 = 180

20 ones = 20 x 1 = 20

Then add both => 180 + 20 = 200

Hence, 18 tens 20 ones = 200.

 It can be possible in only B.C. i.e, Before Christ. That was about 2000 years ago.

 Given, 

 In 1990 B.C = 2000 + 1990 = 3990 years ago, a person is 15 years Old  

=> In 1995 B.C = 2000 + 1995 = 3995 years ago, the same person will be 10 years Old 

Therefore, In 2000 B.C = 2000 + 2000 = 4000 years ago, the same person will be 5 years Old.

After 10 days, the remaining food would be sufficient for the 1000 students for 20 more days

-->If 1000 more students are added, it shall be sufficient for only 10 days (as the no. of students is doubled, the days are halved).

Contra-entry is the entry which effected the both sides in cash book.

It is occured in three times, i.e.,

1.Cash deposited in to bank,

2.Cash withdrawn from the bank for office use, and

3.Receivable cheque deposited in to the bank in another day.

Abiotic and biotic factors are what make up an ecosystem.

Abiotic factors are all nonliving components of an ecosystem. These factors include chemical and geological features such as water or lack of water, soil, rocks, and minerals. Other abiotic factors include physical components such as the temperature and weather affecting the ecosystem.


The biotic factors in an ecosystem include all living things. All plants, animals, fungi, protists, and bacteria within an ecosystem make up that system's biotic factors. The biotic factors can be broken down further into producers, consumers, and decomposers.

The biotic factors present in an ecosystem are highly dependent on the abiotic factors that are present. Even slight changes to either factor can have a major consequence upon the system as a whole.

R is the sister of U

There is no need to use the no of goats i.e (34,398). let initially thete be 1000 goats then 

  1000 -----> 1400 -----> 980 -----> 1274 ----->1146.6

Thus the % increase = (1146.6-1000)/100 x 100= 14.66%