Which of the following scenarios can be classified as a positive feedback loop? 1.increase in blood pressure to reduce the heart rate
2.increase in red blood cell production due to low oxygen levels
3.sweating to cool down skin cells
4.increased platelet production to help blood clotting

D

Explanation:

In order to prevent blood loss, the body needs a mechanism that amplifies the action that leads to clotting in a short period of time. This cascade or enhancement of a process is a positive feedback mechanism.

i am going to guess that it is co2.

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

: -)