An object is thrown vertically upward such that it has a speed 25m/s when it reaches two thirds of its maximum height above the launch point Determine this maximum height.

Explanation:

dropped from maximum height were vertical velocity is zero, the object would have a velocity of 25 m/s in a distance of

v² = u² + 2as

s = (v² - u²) / 2a

s = (25² - 0²) / (2(9.8))

s = 31.887755... m

s/h = 1 - ⅔

s/h = ⅓

h = 3s

h = 3(31.887755)

h = 95.6632...

h = 96 m

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.

3. dark matter

empty space could also be a simple vacuum