A nearsighted person has a far point of 40cm. What power spectacle lens is needed if the lens is 2cm from the eye

The value is

Explanation:

From the question we are told that  

      The value of the far point is  

      The distance of the lens to the eye is  

Generally

Generally the power spectacle lens needed is mathematically represented as

Here is the object distance which for a near sighted person is

And   is the image distance which is evaluated as

=>    

=>    

So

=>      

=>      

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.

im srry but ur wrong the answer is d a smooth rock, some red dirt, and an empty bird's nest.