18. A weightlifter lifts 100 kg from the floor to a height of .2 m. How much work is done by the weightlifter? Acceleration due to gravity is 9.8 m/s/s. W=(ma)d (Do not include units in
your answer.) -

3.2x10^7

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.