The tree died 3696 years ago because 66x5600=369600/10=3696.
Algebra
Since the numbers are the same, you are allowed to add the exponents.

Answer:
Step-by-step explanation:
For similar figures, side lengths (and any other linear measure) are proportional. Areas are proportional to the square of the scale factor for side lengths.
Perimeter 1/Perimeter 2 = CD/EF
21/18 = CD/6
CD = 6(21/18)
CD = 7 . . . cm
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Area 2/Area 1 = (Perimeter 2/Perimeter 1)²
Area 2/98 = (18/21)²
Area 2 = 98(6/7)²
Area 2 = 72 . . . cm²
<h3>Exact area = 12pi - 9*sqrt(3) square inches</h3><h3>Approximate area = 22.1106545749577 square inches</h3>
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Work Shown:
Assuming the chord is horizontal along with the diameter, then this means the two smallest minor arcs are both 30 degrees each. This leaves the northern most arc to be 180-30-30 = 120 degrees in measure
A = area of northern sector (you can think of it as a pizza slize)
A = (angle/360)*pi*r^2
A = (120/360)*pi*6^2
A = 12pi
B = area of triangle
B = (1/2)*side1*side2*sin(included angle)
B = (1/2)*6*6*sin(120)
B = 18*sqrt(3)/2
B = 9*sqrt(3)
C = area of shaded region
C = A - B
C = 12pi - 9*sqrt(3) .... exact area
C = 22.1106545749577 ... use a calculator to get the approximate area