Answer:
0.001
Step-by-step explanation:

The first one
if u need an explanation comment
If you mean 720/10^3, you do 10*10*10. This equals 1000. Now, do 720/1000. This is 0.72, or 72/100, which is your answer.
Answer: You did not include the answer to the equation so 48x+72 is the closet I could get to finding the expression
Hope this Helped!!!