Comment on Activity 1

1. If `x` is the height of the tree, then `x text[/] 7` is the tangent of `61` degrees, or about `1.8`. The height is then `7*1.8=12.6`. A better answer is "about 13 meters," since the data almost certainly don't have 3 significant digits.
   
   Note that if your calculator is set in radian mode (as ours is), you must first convert `61` degrees to `61*pi text[/] 180=1.06465` radians before calculating the tangent. Recall from Section 1.6 that you don't want to round intermediate calculations — you want to keep whatever significance the input numbers have.
2. Before you head outdoors, we note that it is almost impossible to do a sighting with a protractor on the ground. Instead, you can place the protractor on an object at a convenient height for sighting — and then add the height of the object to your calculated height.