Questions

Black  surfaces are good emitters of heat ( They are also good absorbers of heat). If the black surface is rough too, the emitting will be better. So (b) is the correct answer. Shining surfaces reflect back radiation. So if the black surface is also shining the effectiveness of emitting heat is lessened.

Neza-Chalco-Itza is one of Mexico City's barrios(slums). Most of its approximately four million inhabitants live there illegally. Mexico City's slums have been growing for more than 100 years, after the railways allowed new industry to beign in the city. 

Jello is a colloid, a semi-rigid structure i.e, semi-solid suspended in a liquid. When you Heat it up a bit and you'll break the protein bonds of the gelatin and it will liquefy completely and if you freeze, it becomes solid.

Maglev trains are used in Japan, South Korea and China only.

Maglev derived from magnetic levitation using the principle of magnetic repulsion is a system of train transportation that uses two sets of magnets, one set to repel and push the train up off the track as in levitation then another set to move the 'floating train' ahead at great speed taking advantage of no friction. Maglev trains are therefore quieter and smoother than conventional trains, and have the potential for much higher speeds

Despite over a century of research and development, maglev transport systems are in operation in just three countries Japan, South Korea and China.

Hence Maglev -- Magnetic-levitation.

Makaibari is the world's first tea factory and was established in 1859 in Darjeeling, West Bengal. 

It is most expensive tea in India which costs around 1.12 lakhs for 1 kg of tea.

Hence, Makaibari is the costliest variety of Tea.

1.Limitations on the size of data. 

2.Most Microprocessors does not support floating-point operations. 

3.Over heating physically

4. Not bit addressable