The image produced by a concave mirror is

Answer : virtual or real

Mostly real

Explanation:

Concave mirrors can have real images.

“ If the object is further away from the mirror than the focal point, the image will be upside-down and real meaning that the image appears on the same side of the mirror as the object.”

their crystal patterns have been disrupted by stress

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.