Answer:
The height of the tree is is 60m
Step-by-step explanation:
Let's answer a, as it is the only complete question.
We know that the angle of elevation of the top of a tree observed from a point 60m away, is 45°.
We can model this with a triangle rectangle, a sketch of it can be seen below (assuming that you are looking it from the ground).
You can see that the adjacent cathetus to the 45° angle is equal to 60m
And the opposite cathetus is the measure we want to find.
Now you can remember the trigonometric relation:
tan(a) = (opposite cathetus)/(adjacent cathetus).
So to find the height of the tree we need to solve:
tan(45°) = H/60m
This is just:
tan(45°)*60m = H =60m
The height of the tree is is 60m
