What is high altitude sickness? Write itssymptoms.

Explanation

At any high altitude place `gt` 3,500 m Rohtang pass near Manali and Mansarovar, in China occupied Tibet) we observe altitude sickness.
Its symptoms include nausea, fatigue, heart palpitations. This is because in low atmospheric pressure of high altitudes, the body does not get enough oxygen. But, gradually our body compensates low oxygen availability by increasing red blood cell production, decreasing the binding affinity of haemoglobin and by increasing breathing rate.