Answer:
a

b

Explanation:
Generally the force of attraction between this two irons is mathematically represented as
![F = \frac{k * [Q_{Li} ] * [Q_{O} ] }{ r^2}](https://tex.z-dn.net/?f=F%20%3D%20%20%5Cfrac%7Bk%20%2A%20%20%5BQ_%7BLi%7D%20%20%5D%20%2A%20%5BQ_%7BO%7D%20%20%5D%20%20%7D%7B%20r%5E2%7D)
Here k is known as the proportionality constant with value 
substituting -2 for
i.e the charge on oxygen , +1 for
i.e the charge on Lithium and
for r
So


Generally the force of repulsion will be the magnitude but different direction to the force o attraction
So Force of repulsionn is

The other 4 kg of mass may have departed the scene
of the fire, in the form of gases and smoke particles.
Answer:
C. The bug's change in momentum is equal to the car's change in momentum.
Explanation:
As we know by Newton's 2nd law

here we have also know that when car hits the bug then force applied by wind shield on the bug is same as the force applied by the bug on the car's wind shield as per Newton's III law

so we know that

so we have

so correct answer will be
C. The bug's change in momentum is equal to the car's change in momentum.
Answer:
Option (B)
Explanation:
In the stabilizing natural selection, the extreme traits from both the ends are eliminated by natural selection and natural selection favors the intermediate trait. So over time individuals having the intermediate traits are selected over the individuals having extreme traits.
So here the population of the bat which possesses moderate wing length is selected over the individual with extreme traits like individuals with short wings and long wings. As a result, the population of moderate length wing bats increased.
Therefore the correct answer is (B)- stabilizing natural selection.
Voltage = current x resistance
since R is doubled, current must reduce by half.
So,
new current = 120/2 = 60mA