Questions

Black surfaces are good emitters of heat. If the black surface is rough too, the emitting will be better. Shinning surfaces reflect black radiation . So if the black surface is also shining the effectiveness of emitting heat is lessened.

China flicked the switch on the world’s largest floating solar energy plant.  The massive waterborne plant is expected to generate 40 megawatts at one time and could supply electricity for over 15,000 homes. The pioneering project, located in eastern China, is thought to cement China’s status as a top producer of solar energy in the world.  The plant has been built in Huainan city, Anhui Province, by Sungrow Power Supply, a Chinese company specialised in renewable energy.

Here in the given number puzzle, the given numbers follows a pattern that 

1 + 4 = 5 => 1 x 4 + 1 = 4 + 1 = 5 

2 + 5 = 12 => 2 x 5 + 2 = 10 + 2 = 12   

3 + 6 = 21 => 3 x 6 + 3 = 18 + 3 = 21 

Similarly, 

8 + 11 = 96 => 8 x 11 + 8 = 88 + 8 = 96  

Hence, the missing number in the given number puzzle is 96.

southern region is closest to equator and thus receives sunlight for longer duration than any other part of India

You will get the answer in the riddle itself, if you read the riddle carefully.

The riddle says "A cowboy arrives in town on Friday." So Friday is the name of the horse on which he comes. Hence, the only possibility is he arrives on the horse friday on Tuesday, stays for 3 days and leaves on the same horse on Friday. 

There are 10 Non-permanant members of Security Council