Answer:

Step-by-step explanation:




Answer:
Eric's expression is :

and Andrea's is :

In Eric's expression, 20 represents the initial amount of substance with which he has started the experiment.
is the amount of substance left after each time period (in this case, each week).The variable w in this case represents the number of weeks.
Andrea's expression can be written as :

The one outside of parentheses represents the initial amount of the substance. The one inside of parentheses represents 100% of the original amount of the substance. 0.5 represents the 50% of the substance that is lost each time period. The variable w in this case represents the number of weeks.
1. -9 2. -10 3. -100 4. -11 5. 5.-110 6. 204
8. -15 9.-460
Answer:
The 3rd option, so C
Step-by-step explanation:
Answer:
It would be $2.50 on the 25th month I'm sure.
Step-by-step explanation:
I multiplied 0.05 cents by 25 and got $1.25. Then add the original number from the first month, $1.25. Hope this helped. :D