We know that the earth's axis is tilted 23 ½ degrees. On or about June 21 or 22 each year, the summer solstice occurs for those of us who live in the Northern Hemisphere. On this particular day, the sun's rays are striking earth directly, or at 90 degrees, at a latitude approximately 23 ½ degrees north of the equator. If you were at 23 1/2 degrees north latitude on that day, and you looked up at noon, the sun would be directly overhead.

Imagine you have taken a flight north to New York City. Describe the sun rays at exactly noon on the same day of the year.

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.

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me

3. dark matter

empty space could also be a simple vacuum