A touch screen is the only device which works as both an input and an output device among the given options. You view the options available to you on the screen (output) and you then use your finger to touch the option that you have chosen (input).

Hence, Screen is not purely output device.

Covalent type of bonding joins The two hydrogen atoms are joned by Covalent type of bonding.

In this type of bonding, electrons are shared between the atoms in order to fill there valence shells. Thus sharing of electrons take place in between the hydrogen atoms.

Representative money is an item such as a token or piece of paper that has no intrinsic value but can be exchanged on demand for a commodity that does have intrinsic value, such as gold, silver, copper,...

Hence, a Check is an example of representative money.

The third and longest period of prenatal development, extending from the ninth week until birth is Fetal period.

The process of prenatal development occurs in three main stages. The first two weeks after conception are known as the germinal stage, the third through the eighth week are known as the embryonic period, and the time from the ninth week until birth is known as the fetal period.

The book "The Other America" was written by Michael Harrington. The topic of the book 'The Other America' was Poverty was widespread in America.

Protect the consumer from the seller who cheat to sell his product.

The FTC’s Bureau of Consumer Protection stops unfair, deceptive and fraudulent business practices by collecting complaints and conducting investigations, suing companies and people that break the law, developing rules to maintain a fair marketplace, and educating consumers and businesses about their rights and responsibilities.

Another name for the governor of the state is Chief Executive of the state.

And we also know that, The attorney general is the head of the US Department of Justice, The vice president is just under the president of the US and The secretary of state is the head of the US Department of State.

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.