Answer:
12
Step-by-step explanation:

Hey Kiddo.
The domain is the first number of each set.
Domain, 3, 6, -1, 5, -4
Answer at very bottom of picture above
if explanation need comment
This basically says all the steps ! If you have any questions just tell me :)
Answer: The number is 40
Step-by-step explanation:
We will set up an equation where 4/5 is being multiply by the number to get 32. we will represent that number by x
4/5 * x = 32 solve for x
4/5x = 32
0.8x = 32
x = 40