Questions

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

The water rise in a capillary tube dipped in water is such that the weight of water in the tube above the surface of water in the vessel is equal to (balances) the upward force due to surface tension. So it is clear that if the the bore (radius) to the tube is decreased, the height of the water column in it must be greater.  So, (a) is correct.

Ecology is the branch of science which deals with the study of Ecosystem (relation between the Organisms and their Environment.)

Raipur’s Swami Vivekananda Airport was ranked first in Customer Satisfaction Index (CSI) Survey among 49 airports in the country. It has achieved 4.84 score on a five point scale index. It was followed by Udaipur (2nd), Amritsar (3rd) and Dehradun (4th) airports which have scored 4.75, 4.74 and 4.73 respectively. This is third consecutive time in the past two years, Raipur airport has received this recognition.

Normal Gas welding use oxygen-acetylene.

Depending on what materials you are welding, there are some more options that might be used.

For example - MIG/TIG use Argon, MAG use an argon-something mix.