Assuming that the long term rate of displacement along the san andreas fault (about 3.5 cm/year) remains the same and that the location of the fault remains the same, how long would it take los angeles (on the west side of the fault) to move north 620 kilometers to the position of san francisco (on the east side of the fault)?

17.71 years

Explanation:

As the crust of the San Andrea is continuously moving due to the tectonic activity and is the main manifest of the tectonic boundary of the North America and the pacific plate. This fault along with the pacific plate will move towards the Los angles and eastern San Francisco as it moves about 3.5 cm per year. As  1 km equals to about 100 000 cm , then the distance of 620 km =  62, 000,000 cm  and 62,000,000 will be divided by 3.5 equal to  17. 71 years to collide with the eastern side.

Answer:   [b]:   "cultural" .

C. naturally in the environment