Answer: A) 80 Explanation: Next number of the sequence 1, 4, 12, 32,... 1 = 2 x 20 4 = 2 x 21 12 = 3 x 22 32 = 4 x 23 80 = 5 x 24.

Answer: C) Afforestation Explanation: The four most common soil erosion prevention methods are vegetation, geotextiles, mulch, and retaining walls. By planting grass in areas of concentrated water flow, farmers can prevent much of the soil erosion that results from runoff, as the grass stabilizes the soil while still providing an outlet for drainage. Preventing soil erosion is critical in protecting your property and exposed soil, whether from wind, weather, running water, and even the after-effects of the forest fire.

Answer: C) Database Explanation:

Photoautotrophs are those organisms that can make their own food using sun light with the help of the process of photosynthesis. Plants can prepare their own food using sunlight. Hence they are Photoautotrophs.

Answer: B) Charcoal Explanation: It is Charcoal which is black when we buy it or when not being used. It gets red in appearance when put in use means to say when burning. And eventually when it's been consumed by fire or after getting burned out or used up, changes into ashes which look grey in color.

Answer: C) Cross-Demand Explanation:

A Sandal. It has sticking strips to make them fit for our feet. If you bind them only you can start walking or other wise it comes out.

Answer: B) 12, 18, 36, Explanation: The Multiples of 6 are 6, 12, 18, 24, 30, 36, 42, 48, 54, 60. The Multiples of 4 are 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60. The Common Multiples of 4 & 6 upto 60 numbers are given as 12, 24, 36, 48, 60.