Questions

A promise. 

The Promise made to somebody by you can be break but you cannot touch it.

Prices do not reflect the full social cost of production is an example of Market failure.

A market failure occurs when the supply of a good or service is insufficient to meet demand. This results in an inefficient distribution of resources among market participants.

It also occurs if externalities are not accounted for.

If a firm fails to maximize its profits this is not a general market failure.

Most producers use sun light for making their energy in the process of photosynthesis. The energy they prepared is sugar and glucose. 

17 and 119

Uttar Pradesh state government to install 221-Metre Bronze Statue Of lordRam In Ayodhya.

For neutral atoms, the periodic trends in atomic size can be described like this

Atomic size decreases when going from left to right across a period,
Atomic size increases when going from top to bottom down a group.

Let's use these trends to try and figure out which atom would have the largest radius.

If you look at elements that are located in the same group, potassium will have a larger atomic radius when compared with sodium. Likewise, bromine will have a larger atomic radius when compared with chlorine.

Now focus on potassium and bromine. Since potassium is located at the start of period 3, and bromine at the end of the same period, potassium will have a larger atomic radius than bromine, and thus the largest atomic radius of the four given atoms.