(x+4) , (x+12) ,(x-1) and(x+5) are in proportion. find the value of x

Ateam of researchers calculates that a glacier will melt completely away in the next 100 years. which land structure will most likely be left behind after the glacier melts?

What happens to rock when acid reacts with it?

In the late 1990s, brazil’s poor people protested about crowded cities land distribution mining permits industrial pollution