Abird sitting high in a tree is an example of an object with what type of energy?

a. potential energy because it has the ability to do work.
b. kinetic energy because it has the ability to do work.
c. potential energy because it is doing work.
d. kinetic energy because it is doing work.

a. potential energy because it has the ability to do work.

Explanation:

Here when object is in motion then the energy stored in it is known as kinetic energy

while if an object is at rest at some height above the surface then the energy stored in it is known as gravitational potential energy

this energy is stored in the object and it shows the ability to do work

when the object is dropped from some height then this gravitational PE will convert into kinetic energy

so here correct answer will be

a. potential energy because it has the ability to do work.

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.