1) Calcule as potências: a) 4-2 =
b) 4-3 =
c) 5-1 =
d) 3-3 =
e) 10-2 =
f) 10-3 =
g) 2-5 =
h) 7-1 =
i) 1-18 =​

From the top of a tree a bird looks down on a field mouse at an angle of depression of 50°. if the field mouse is 40 meters from the base of the tree, find the vertical distance from the ground to the bird's eyes.