Questions

Tongue. Yes tongue tastes better than it smells as it can't smell.

A redox reaction is a type of reaction which involves transfer of electrons among two species. This reaction is also called oxidation-reduction reaction.

In oxidation process, there is an increase in oxidation state of an atom, ion or molecule by losing the electrons.

In reduction process, there is a decrease in oxidation state of an atom, ion or molecule by accepting the electrons.

1)

In this reaction, Ba undergoes oxidation and Cl undergoes reduction.
This reaction is redox reaction.
In this reaction, oxidation number of Ba increases from 0 to +2 . So, Ba undergoes oxidation. The oxidation number of Cl decreases from 0 to -1. So, Cl undergoes reduction.

2) 

From this above reaction, it is clear that Aluminum undergoes oxidation and silver undergoes reduction.
Due to this, this reaction is redox reaction.

In this reaction, oxidation number of Aluminum increases from 0 to +1. So, aluminum undergoes oxidation. The oxidation number of silver decreases from +1 to 0. So, silver undergoes reduction.

3)

In this reaction, Mg undergoes oxidation and Br undergoes reduction.
This reaction is redox reaction.
The reactions 1, 3 and 4 are redox reactions.
In this reaction, oxidation number of Mg increases from 0 to +2 . So, Mg undergoes oxidation. The oxidation number of Br decreases from 0 to -1 . So, Br undergoes reduction.

Hence all the above reactions are redox reactions.

Northern California

The air forces of China and Pakistan began a joint training exercise SHAHEEN and deployed their latest fighter jets and AWACS aircraft. 

Speed has been identified as a key risk factor in road traffic injuries, influencing both the risk of a road crash as well as the severity of the injuries that result from crashes.

Speeding is a factor in 30 % of all fatal accidents.

The potable water is the water, which is tested and safe for drinking purpose and cooking preparations. The water is tested and purified in industries. So, the potable water is costly.

Hence, Access to potable water is most heavily limited by money.

In the above given options, Retrovirus is the only virus which is not associated with cancer. Here the viruses which are associated with different types of cancer. They are:

Hepatitis virus which is associated with Liver cancer

Papillomavirus which is associated with Cervical cancer

Epstein-Barr virus which is associated with Burkitt's lymphoma.