What does it mean when when we that say that the air get's thinner​

How many countries have portuguese as a national language?

What is the general rule about surface currents? cold water flows along the ocean floor towards the equator. the east coasts of continents have cold surface currents, and the west coasts of continents have warm surface currents. seasonal and constant offshore winds create significant upwelling along the west coasts of south and north america and africa. the west coasts of continents have cold surface currents, and the east coasts of continents have warm surface currents.

You are a scientist who has been sent on a special mission to study plants and animals in south asia! your destination is an important forest in eastern india. you need to travel to 17°n latitude and 83°e longitude.