Final answer:
The problem involves using trigonometry to calculate the angle of sight for Friend 3 looking down from a tree at Friend 1. By setting up a right triangle and using the arctan function, we can determine the angle based on the heights and distances involved.
Step-by-step explanation:
The student is asking for help calculating an angle of sight, which involves using trigonometry. Specifically, we are looking for the angle that Friend 3 must look down from atop a 60 ft tree to see Friend 1, who is 40 ft horizontally away (since the tree is halfway between Friend 1 and 2 who are 80 ft apart).
We set up a right triangle with the tree height as the opposite side (60 ft) and the distance to Friend 1 as the adjacent side (40 ft). We can then use the tangent function, which relates the opposite side to the adjacent side in a right triangle through the angle of interest. The equation is tangent (angle) = opposite/adjacent. To find the angle, we need to use the inverse tangent function, also known as arctan or tan-1.
By calculating arctan(60/40), we can find the angle of sight. Let's do the math: arctan(1.5) or arctan(60 ft / 40 ft), which will give us the angle in degrees that Friend 3 is looking down at Friend 1.