Questions

Two series alternate here, with every third number following a different pattern.
In the main series, 4 is added to each number to arrive the next.
In alternate series, 5 is subtracted from each number t arrive the next number.
Here in the main series 
3 + 4 = 7
7 + 4 = 11
11 + 4 = 15
15 + 4 = 19

In alternate series 
24 - 5 = 19
19 - 5 = 14...

The resistance of metallic conductors e.g, platinum, increases with rise of  temperature . The increase in temperature results in a decrease of current which can be recorded in a galvanometer if the conductor is included in an electrical circuit. Thus the temperature can be known; platinum resistance thermometer is used generally for accurate scientific work. When two dissimilar metals are joined at the ends, and these ends are subjected to a difference of temperature, a current flows through the metals. Greater the difference of temperature , greater the current. So the curent strength can form the basis for measuring the difference in temperature. And when one of these temperatures is known, we can calculate the other.

Labor unions are associations of workers who pursue common objectives. Workers use this platform to bargain collectively on behalf of the majority of workers.

$pwd - present working directory

The World Environment Day (WED) is observed every year on June 5 to raise awareness about forests and wider issues of environmental protection. The 2017 theme is ‘Connecting People to Nature’. It implores us to get outdoors and into nature, to appreciate its beauty and to take forward the call to protect the Earth that we share. The host country for the WED 2017 is Canada, where the official celebrations take place.

WBR that is World Book of Records, the London based organization that focuses on maintaining and cataloging the world records has awarded the title of 'Most visited place in the World' to the famous Golden Temple. This holy Shrine has recorded quite an uplift after the successful Heritage street project carried out by the Amritsar department. 

Sri Harmandir Sahib, also known as Golden Temple and the Darbar Sahib, is the holiest Gurdwara and the most important pilgrimage site of Sikhism. It is located in the city of Amritsar, Punjab, India.