How sunspot are formed ?

not sure

Explanation:

lol

Sunspots are magnetic in nature. They are the places ("active regions") where the Sun's magnetic field rises up from below the Sun's surface and those magnetic regions poke through. ... Sunspots are formed continuously as the Sun's magnetic field actively moves through the Sun.

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.