A weather balloon is rising vertically (in a perfectly straight line!); a camera on the ground 100 meters from the point at which the balloon was released is tracking the ascent. At what rate is the distance between the camera and the balloon changing when the balloon is 75 meters high

this is an example of "committed" time.

committed time, as contracted time, takes need over essential and available time since it is seen as profitable work. it alludes to the time allotted to keep up a home and family. at the point when a man is commuting using committed time this individual may feel that the drive is an obligation to family, for example, strolling youngsters to class or driving a mate to work. contracted and committed time clients may feel that their commute could really compare to the commute of important or leisure time clients on the grounds that their commute is profitable work. in this manner, they might be more disposed to pick a mechanized method of movement.  

i really dont know but i will try okay.

so i think u would just add all them up and get your answer..