A hiker travels 300 m [N], turns around and hikes 550 m[S], and then finds out he has to hike back another 50.0 m IN). He manages to do this in 7200 seconds (equivalent of 2 hours).
What is the total distance traveled by the hiker?

900 m

Explanation:

Given that,

A hiker travels 300 m [N], turns around and hikes 550 m[S], and then finds out he has to hike back another 50.0 m  [N].

We need to find the total distance travelled by the hiker.

Let north be positive and south be negative direction.

Distance = total path covered

D = 300 + 550 + 50

D = 900 m

So, the required distance is equal to 900 m.

photocells convert light energy to electricity

305.7

explanation:

density =m/v

density =917/3.00

density = 305.

approximately = 305.7

in four significant figures