Substances that have a ph of less than 7 are acidic for each ph unit lower the acidity is 10 times greater for example normal precipitation a slightly acidic add a 5.6 ph
if acid precipitation were measured at 4.6 ph it would be 10 times more acidic than normal precipitation how many times more acidic would precipitation at 3.6 ph be than normal precipitation ?

Here is a picture  of the net. its 4 squares in a row diagonal and on the third draw one square aove and under

Humans have survived and thrived in mexico city by using technology to create greater access to land. when the spanish conquered the aztec capital, tenochtitlan, in the 16th century, they built mexico city by draining the lakes and filling in the lake water to create more arable land for agriculture. this technique of land reclamation has continued to be fundamental to human civilization in mexico city. 

The scientist can conclude that there is a decrease in the natural resources due to human activities. because of innovation and modernization of the environment, then there goes pollution and other bad effects that destroys the natural resources.