HURRY! Only 5 minutes to answer! What causes droughts?

1. Humans
2. Natural Events
3. Aliens from outer space
4. Like with many things about our planet it is caused by Humans and Nature

The is 4. Like with many things about our planet it is caused by Humans and Nature, I belive because droughts can be caused by humans and nature.

Explanation: Humans cut trees down trees , which trigger droughts to happen. Also because when humans cut a widespread of trees down just for fuel, it can potentially reduce the soil's ability to hold water ... triggering droughts to happen. But also droughts can happen just by nature.

when [oh-] is 10-5  m, and [h3o+] is 10-9  m, the poh is 5 and ph is 9. again in both cases the sum of ph and poh is 14. however, the hydrogen ion concentration is not always going to be equal to exactly 1 x 10 raised to a negative number. for example, we skipped over the value of 2.0 x 10-7.

in cartography, a contour line (often just called a "contour") joins points of equal elevation (height) above a given level, such as mean sea level. a contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness or gentleness of slopes.

explanation: