Solution

25360

First name
Alice and Phoebe
School
Guildford High School
Country
Age
11

Go to a tree that is quite tall and you would not be able to measure from the ground yourself. Measure 45 degrees with a protractor from the ground. Move back until the top of the angle is pointing at the top of the tree. Measure how far you are from the trunk of the tree and that is how tall the tree is.