Sixth grade
Because if you divide their total profit by the total amount of hours they worked, you would find that the sixth grade's income per hour is the highest.
Sixth grade: 170÷5=34
Seven grade: 112÷4=28
Eighth grade: 192÷6=32
Answer:
See attached image for the drawing of the first four trees (circled in green)
The patterns is:
x = 2+3n and y= 3+2n
Position of 7th tree is: (20,15) (circled in orange in the image)
Step-by-step explanation:
Starting at the location (2,3) the next x and y positions are given by:
x = 2+3n since the horizontal position needs to be increased by 3 units on each iteration,
and y= 3+2n since the vertical position needs to be increased by 2 units on each iteration
being n= 1 through 6 (to account for the next 6 trees that need to be planted)
With such pattern, the location of the seventh tree would be:
x = 2 + 3*6 =2 + 18 = 20
y = 3 + 2*6 = 3 + 12 = 15
That is, the point (20,15) on the plane.
Also see attached image.
Hey!
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Solution:

Cube the coefficients.

Multiply the exponents.

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Answer:
Option D.
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Hope This Helped! Good Luck!