Atmospheric pressure at aheight of about 6km decreases to nearly half of its value at the sea level , though the height of the atmosphere is more than 100 km .

Explanation

The variation of air density with height is non - linear. So, pressure also deos not reduce linearly h is given by `P=P_(0)e^(-alphah)` where `P_(0)` represent the pressure of air at sea level and `alpha` is a constant.