D. <span>When placed together in pairs for study, no pair of Abert's squirrel and Kaibab squirrel result in offspring.</span>
Answer:
Work done, W = 6 J
Explanation:
It is given that,
Force of gravity acting on the book, weight of the book is 15 N
We need to find the work done in lifting the book straight up for a distance of 0.4 meters.
The weight of the book is acting in downward direction and the book is lifted straight up, it means angle between them is 180 degrees. Work done is given by :

So, the magnitude of work done in lifting the book is 6 joules.
Answer:
Decreases by
times
Explanation:
The intensity of a sound is defined as the energy of the sound that is flowing in an unit time through the unit area which is in the direction that is perpendicular to the direction of the sound waves movement.
The intensity of energy is described by the inverse square law. It states that the intensity varies inversely with the distance square of the distance.
In other words, the sound intensity decreases as inversely proportional to the squared of the distance. i.e. 
In the context when the distance was 3 m, the intensity of the sound was = 
But when the distance became 6 cm or 0.06 m, the sound intensity decreases by = 
=
times
It is overhead at the equator, it is because the sun ray’s
will be moving vertically as this will be directed at the equator. It is
because if it moves vertically, it will hit or overhead the equator and this
usually happens in spring and fall.
Answers :
1. All points of a conductor are at the same potential. - True
2. Charges prefer to be uniformly distributed throughout the volume of a conductor. - False
3 The electric field inside the conducting material is always zero. -True
4.Just outside the surface of a conductor, the electric field is always zero. - False