Answer:

Kelly is correct.
Step-by-step explanation:
One person is able to plant 4 trees
Let x be the number of people
y be the number of trees
The situation is represented by

5 people are able to plant 20 trees

So, the situation is represented by 
Hence, Kelly is correct.
It is the right answer........
Full working out shown from step 1 to last.
follow it and you get 24 square feet as final answer. Good luck in other questions!!!
Answer:
The price of the admission is 15.
Step-by-step explanation:
From the information given, you can write the following equations:
a+3e=45 (1)
a+5e=65 (2), where:
a is the admission cost
e is the exhibition cost
First, you can solve for a in (1):
a=45-3e (3)
Second, you can replace (3) in (2):
45-3e+5e=65
45+2e=65
2e=65-45
2e=20
e=20/2
e=10
Finally, you can replace the value of e in (3):
a=45-3e
a=45-3(10)
a=45-30
a=15
According to this, the price of the admission is 15.