Answer: D) All the above Explanation: A greenhouse gas (GHG) is any gas in the atmosphere that absorbs and emits radiation in the thermal infrared range.   The increase in average global temperatures that results from an enhanced greenhouse effect. Effects of increased greenhouse gas emissions: Increases in the different greenhouse gases have other effects apart from global warming including ocean acidification, smog pollution, ozone depletion as well as changes to plant growth and nutrition levels.

Answer: C) United Nations (UN) Explanation: The United Nations (UN) has declared 2017 as the "International Year of Sustainable Tourism for Development" to celebrate and advance the commitment of the tourism division to building a superior world.The International Year aims to support a change in policies, business practices and consumer behavior towards a more sustainable tourism sector that can contribute effectively to the Sustainable Development Goals (SDGs).

12 S of Z represents 12 Signs of the Zodiac.   It is similar to the 1. 52 W in a Y        -  52 weeks in a year 2. 3 H in a C          -  3 Hands in a Clock 3. 3600 S in an H   -  3600 Seconds in an Hour 4. 5 O in the W      -   5 Oceans in the World

Answer: A) 25 sq.cm Explanation: Given length of the rectangle = 3 cm Breadth of the rectangle = 4 cm Then, the diagonal of the rectangle D = 32 + 42 = 25 = 5 Then, it implies side of square = 5 cm We know that Area of square = S x S = 5 x 5 = 25 sq.cm.

Answer: A) TRUE Explanation: True, Water is a Pure substance and not a mixture.   We know that, A mixture is when two or more substances combine physically together. You can find that the mixture retains the properties of the original components. In water, two hydrogen atoms combine with one oxygen atom chemically, forming a new substance that has properties different from hydrogen alone or oxygen alone.   Therefore, water is not a mixture; it is a compound and it is pure.

Answer: B) Helium Explanation: Helium has the highest First Ionization Energy in the Noble Gases group. Ionization Energy :: Ionisation energy is the energy required to remove one mole of electrons from one mole of gaseous atoms. Atoms are more stable when they have full valence shells. Noble Gases have a very stable electron configuration, therefore, they have the highest amount of ionization energy within their periods. It decreases down a family because electrons farther from the nucleus are easier to remove. Ionization Energy levels of Noble Gases group in Descending Order :: He, Ne, Ar, Kr, Xe, Rn

Answer: D) 125 Explanation: Methods for selecting 4 questions out of 5 in the first section = 5 x 4 x 3 x 2 x 1/4 x 3 x 2 x 1 = 5. Similarly for other 2 sections also i.e 5 and 5 So total methods = 5 x 5 x 5 = 125.

The boat which is overtaken must give way to the boat which is overtaking.