Answer:

Step-by-step explanation:
If the temperature drops, then you must have subtract amount of drop from initial temperature.

The correct answer is the first one.
Answer:
C. 
D. 
Step-by-step explanation:
C. 



D. 




Answer: I think it’s the plants.
sorry if it’s not right
X+y=31.5
x-y=5.25
add 2 equations
x+y+x-y=31.5+5.25
2x=36.75
x=18.375
y=31.5-18.375=13.125
check : 18.375+13.125=31.5, 18.375-13.125=5.25
so
Answer:
18.375 and 13.125