A because if he started at negative ten you would add the 10 he increased. When you add those two together you get 0.
-10+10=0
9 days ago, the mold covered an area of
.
Today (after 9 days), the mold covers an area of
.
<em>What is the increase in area?</em> It went from 3 to 9. So the increase is
.
Now, we need to find <em>rate of change</em>. It means to find how much the area increased every day over the past 9 days. We simply divide <em>the increase (6)</em> by the <em>total number of days (9)</em> to find the rate per day. So we have,

ANSWER: Change of Rate =
per day
Answer:
c alternate interior angles theorem
Step-by-step explanation:
e2020
Answer: Ron take approximately 4.2 hours to make 100 crusts alone.
Step-by-step explanation:
Since we have given that
Number of hours taken by Ron before Harold = 1.2 hours
Number of hours taken by Ron and Harold together = 1.8 hours
We need to find the number of hours taken by Ron alone i.e. 'x'.
Let number of hours taken by Harold alone be '1.2-x'.
Let work done by Ron alone = 
Work done by Harold = 
According to question, we get that

x-1.2 does not satisfied with x = 0.5 so, x = 4.2
Hence, Ron take approximately 4.2 hours to make 100 crusts alone.