Questions

Human eye resolution is 576 Mega Pixels approximately.

Dragon flies have legs but they cannot walk.

It is the protocol the routers in neighboring autonomous systems use to identify the set of networks that can be reached within or via each autonomous system.

A voting machine is a machine used to register and tabulate votes.

In the given options, It was invented in 1898 is the false statement as it was actually invented in 1875 with some faults in it.

Nachiket Mor Committee on Comprehensive Financial Services for Small Businesses and Low Income Households (commonly known as the Nachiket Mor Committee) was an expert committee formed by Raghuram Rajan on 23 September 2013, after he was appointed as the governor of the Reserve Bank of India (RBI). It was headed by Nachiket Mor.

An ionic bond is a chemical bond between two atoms in which one atom seems to donate its electron to another atom.

Here in the given compounds, the compound that contains ionic bond is CaO, Calcium oxide.

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.