You are standing on the ground, watching a bird fly away horizontally at a rate of 9 meters per second. the bird is initially located 25 meters above your head. let θ be the angle measured from the vertical direction to the direction from you to the bird. how fast (in radians per second) is θ changing when the horizontal distance between you and the bird is 12 meters

Explanation:

horizontal distance traveled by the bird is equal to be x

given,

height of the bird above his head = 25 m

angle between them is equal to θ

d² = x² + y²

now,

at x = 12 m

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.