Answer:
I believe its a and c but my notes are all kinds of messed up so im sorry if its wrong
Explanation:
Answer:
The time taken for the paint ball to hit the ground is 
The distance of the landing point from the tower is
Explanation:
From the question we are told that
The height of the tower is 
The speed of the paintball in the horizontal direction is 
Generally from kinematic equation we have that

Here u is the initial velocity of the paintball in the vertical direction and the value is 0 m/s , this because the ball was fired horizontally
a is equivalent to 
t is the time taken for the paintball to hit the ground
So

=> 
Generally the distance of its landing position from the tower is

=> 
=>
Answer: ionic compound
Explanation:
An ionic compound is formed when one element completely transfers its valence electron to another element. The element which donates the electron is known as electropositive element and forms a positively charged ion called as cation. The element which accepts the electrons is known as electronegative element and forms a negatively charged ion called as anion.
For formation of sodium chloride:
Electronic configuration of sodium:
![[Na]=1s^22s^22p^63s^1](https://tex.z-dn.net/?f=%5BNa%5D%3D1s%5E22s%5E22p%5E63s%5E1)
Sodium atom will loose one electron to gain noble gas configuration and form sodium cation with +1 charge.
![[Na^+]=1s^22s^22p^63s^0](https://tex.z-dn.net/?f=%5BNa%5E%2B%5D%3D1s%5E22s%5E22p%5E63s%5E0)
Electronic configuration of chlorine:
![[Cl]=1s^22s^22p^63s^23p^5](https://tex.z-dn.net/?f=%5BCl%5D%3D1s%5E22s%5E22p%5E63s%5E23p%5E5)
Chlorine atom will gain one electron to gain noble gas configuration and form chloride ion with -1 charge.
![[Cl^-]=1s^22s^22p^63s^23p^6](https://tex.z-dn.net/?f=%5BCl%5E-%5D%3D1s%5E22s%5E22p%5E63s%5E23p%5E6)
The cations and anions being oppositely charged attract each other through strong coloumbic forces and form an ionic compound.