B)is pills everything to the surface of the earth not sure about A
The force between the two objects is 19.73 nN.
<u>Explanation:
</u>
Any force acting between two objects tends to be directly proportional to the product of their masses and inversely proportional to the square of the distance between the two objects. And this kind of attraction force between two objects is termed as gravitational force.
So if we consider
and
as the masses of both objects and let d be the distance of separation of two objects. Then the force between the two objects can be determined as below:

As gravitational constant
,
= 20 kg and
= 100 kg, while d = 2.6 m, then

Thus, we get finally,

As we know, nano denoted by letter 'n' equals to 
So the force acting between two objects is 19.73 nN.
It is salt water because they are two things combined together.
Answer:
The number of turns, N = 1750
Explanation:
It is given that,
The inner radius of a toroid, r = 12 cm
Outer radius, r' = 15 cm
The magnetic field at points within the coils 14 cm from its center is, 
R = 14 cm = 0.14 m
Current, I = 1.5 A
The formula for the magnetic field at some distance from its center is given by :



N = 1750
So, the number of turns must have in a toroidal solenoid is 1750. Hence, this is the required solution.