By what method we can know what the receiver understood or got the message

Which of the following is not computer hardware?

Which of the pollutants can cause cancer in humans?

What is called for the chemicals which emit with vinyl floors?

Look at this series: 36, 34, 30, 28, 24, ... What number should come next?

If A is the brother of B; B is the sister of C; and C is the father of D, how D is related to A?

Discussion Method can be used when:

The present annual examination system:

A researcher divides the populations into PG, graduates and 10 + 2 students and using the random digit table he selects some of them from each. This is technically called 

A researcher divides his population into certain groups and fixes the size of the sample from each group. It is called

Which of the following shows a positive facial expression?

By what method we can know what the receiver understood or got the message

Which of the following is not computer hardware?

Which of the pollutants can cause cancer in humans?

What is called for the chemicals which emit with vinyl floors?

Look at this series: 36, 34, 30, 28, 24, ... What number should come next?