I'd say b, but i'm not 100 percent sure.<span />
Answer:
[Ar] 3d10 4s2 4p3 is shorthand, 1s22s22p63s23p63d104s24p3 long hang
Explanation:
The shorthand is made using the lowest & closest noble gas, and picking up where it leaves off as follows, and longhand is made from a followed pattern you can easily find

Actually Welcome to the Concept of the Ionic bonds.
Since Sodium (Na) is a cation and Chlorine (Cl) is a Anion, they both form a Ionic bond called as NaCl (common salt)
So answer is, Na and Cl
The statements that are true regarding a catalyst are as follows:
It undergoes no permanent change during a reaction
It does not participate in a chemical reaction
What is a catalyst?
A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process.
A catalyst increases the rate at which a chemical reaction occurs by decreasing the activation energy of the reaction.
Since a catalyst is not used up in the reaction, the following statement applies:
It undergoes no permanent change during a reaction
It does not participate in a chemical reaction
Learn more about catalyst at:
#SPJ1
The answer is ....... 47/10^8