Questions

Agriculture would be a good example of a purely competitive industry.

Ammonia is a base. One adding ammonia to water,the resulting solution will become basic. pH of an alkaline solution is 7. So the pH will increase

Therefore the answer for What travels around the world but stays in one spot is STAMP or any other thing that acts as a stamp does.

Ex. the letter in the envelope etc...

Since, Several things have the possibility, but the word travel evokes that it would move. 

The combined gas law states that the ratio between the pressure-volume product and the temperature of a system remains constant.

Hence it depends on all the three Volume, Temperature & Pressure.

A simple rule concerning water and electrolyte regulation is water passively follows salt.

It is a protocol used to advertise the set of networks that can be reached with in an autonomous system. BGP enables this information to be shared with the autonomous system.