URGENT. Which is an exponential decay function? ANSWER GETS BRAINLIEST.

C

Step-by-step explanation:

For the first one, there is a ratio of change greater than one so that is exponential growth.

The second one has exponential decay but its x is negative making it actually exponential decay even if graphed.

The third one has positive growth over an interval of negative x, so in terms of  x there is exponential decay.

The fourth one is neither and if graphed is just points as there is a specific solution set.

In conclusion, the third is exponential decay!

Hope this helps :)

X = 2 cm

Volume = Bh= 8×5×1/2×X= 80

X = 80/20 = 4