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Answer
Figure This!
 

Answer:
Only the coast redwood and the giant sequoia are clearly big enough.

If two-feet "walls" are enough to hold up the tree around a six-foot wide car, then the black willow, the coast Douglas fir, the sugar pine, and the white oak are big enough as well.

 

Complete Solution:
To find the diameter of a circle when you know the circumference, you divide the circumference by (pi, about 3.14). For example, the black willow has a girth of 400 inches and since 400 ÷ 3.14 is about 127, the black willow is about 127 inches wide, enough for a car to drive through and still leave at least 2 feet on each side.

Tree
Girth
(4.5 ft above ground in inches)
Diameter
(girth ÷ )
Height
(in feet)
American Beech
279
89
115
Black Willow
400
127
76
Coast Douglas Fir
438
139
329
Coast Redwood
867
276
313
Giant Sequoia
998
318
275
Loblolly Pine
188
60
148
Pinyon Pine
213
68
69
Sugar Maple
274
87
65
Sugar Pine
442
141
232
White Oak
382
122
96

 

 
       
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