You need more information to solve this problem. The length of a shadow depends on the angle of the sun which depends on the time of day.
Chat with our AI personalities
The shadow:object ratio is 1:1 so the tree is 63 feet high.
488 cm
27.3 feet
25 meters because 25/20 = 15/12 which is the tangent ratio.
If the tree is T ft high, then T/21 = 8/3 so that T = 21*8/3 = 56 feet.