The eye of a category 2 hurricane is 450 nautical miles away and forecast to come ashore at your coastal location. the tropical storm-force winds extend 150 nautical miles. the hurricane is moving at 15 knots. if it maintains forward speed, how long before tropical storm-force winds begin to affect your community?

We are given that the eye of the storm is 450 nautical miles away and the storm force extends up to 150 nautical miles. So when the eye is 150 miles away from the community, the outer edges of the storm winds will begin to affect the community.

Distance the eye has to travel, d = 450 – 150 = 300 nautical miles

Since t=d/s

where s = 15 knots = 15 nautical mile/hr

t = 300/15

t = 20 hours

Mantle convection is the process that drives plate tectonics. the theory of plate tectonics states that the crust is divided into plates that float on the semi molten mantle below. the circular motion of the magma as it slowly rises and falls or move though convection cells drags the plates along causing them to move. the heat source in the lamp would represent the earth's core. the core is the source of energy that drives convection in the mantle. the lava represents molten magma under the earth's surface. if the lava lamp had floating pieces they would move as the circular motion of the lava in the lamp as it rises and falls would move them along the surface. these floating pieces would represent pieces of the earth's crust. 

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