An experiment will be conducted to determine whether children learn their multiplication facts better by practicing with flashcards or by practicing on a computer. Children who volunteer for the experiment will be randomly assigned to one of the two treatments. Because the children's gender may affect the outcome, there will be blocking by gender. After practice, the children will be given a test on their multiplication facts. Why will it be impossible to conduct a double-blind experiment?A. The experimenter will know whether the child is a boy or a girl and whether he or she used flash cards or the computer. B. The child will know whether he or she is a boy or a girl. C. The child will know whether he or she used flashcards or the computer. D. The person who grades the tests will know whether the child was a boy or a girl. E. The person who grades the tests will know whether the child used flashcards or the computer.

C. The child will know whether he or she used flashcards or the computer.        

Explanation:                                                            

The double-blind experiment is described as an experiment in which both the individuals i.e, the person or researcher who is implementing or conducting the experiment and the participants or subjects are not being aware of the fact that which person is getting or receiving the "experimental treatment". Therefore, the main aim of the double-blind experiment is to make sure that the results of the experiment are not biased.

The correct answer is option C.

the united states has a federal government. the president is the head of the federal government of the united states. however, each state forms its government for administration purposes. the powers of the state governments are exercised within restricted state boundaries. and citizens participate in this government by voting.