When plate tectonics cause cracks to form, scientists expect entire continents to fall into the earth volcanoes can occur a large rift usually remains and is never filled in most likely the country of mexico will separate from the continental united states

I think it's the 2nd one,  Volcanoes can occur.

The answer is B.

During plate tectonics, cracks may occur in the earth crust that causes magma to rise up from the mantle. The cracks may also cause cracks to form on the crust that makes outlet channels for the magma in magma chambers. These result in volcanic eruptions on the surface of the earth that form volcanic features such as mountains.

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

according to question, we have said that if the population has twice its initial population, then it becomes

so, time taken to reach this above mentioned population is given by

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.

massxgravity x heght=weightxheight= pe

4900=490xh

h=10