Arunner sprints 550 feet in 100 seconds. if the runner can hold this pace for an hour
and a half without stopping, what distance, in kilometers, will the runner have traveled?
(1 m = 3.28 ft)

Distance traveled is 9.055 km

Speed is given by dividing distance by time.

The distance given is 550 ft and the time is 100 seconds.

Therefore; Speed = 550 ft ÷ 100 sec

                              = 5.5 ft/sec

We can calculate the distance the runner covered in one and half hour.

Time = 1.5 hours

But 1 hour = 3600 sec

1.5 hours = (1.5 × 3600)

               = 5400 sec

Distance is given by multiplying speed and time

Thus; Distance = 5.5 ft/sec × 5400 sec

                         = 29700 ft

But; 1 m = 3.28 ft

1000 m = 1 km

Therefore; 29700 ft will be equivalent to

 = 29700 ft/3.28 ft

= 9054.878 M

but 1000 m = 1 km

Thus, distance = 9054.878 ÷ 1000 m

                        = 9.055 km

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.