Answer:
The correct option (c) "is held together by ionic bonds".
Step-by-step explanation:
Table salt is NaCl. It is a combination of Sodium and Chlorine.
There is 1 valance electron in sodium. Its electronic configuration is 2,8,1
The electronic configuration of Chlorine is 2,8,7. It means that it needs 1 electron so that its octet gets completed.
Na transfers one electron to Cl. It becomes Na⁺. Cl gains one electron From Na. It becomes Cl⁻.
As a resuslt, Na⁺ and Cl⁻ forms. Both Na and Cl are ions. They held together by ionic bonds.
Your answer would be approximately 254.5 if you round since 9^2 times pie you would get such
Answer:
-¹²/₅
Step-by-step explanation:
Let cos a = -⁵/₁₃
Then tan a = sin a/cos a
= [√(1 - cos²a)]/cos a
= {√[1 - (-⁵/₁₃)²]}/(-⁵/₁₃)
= -[√(1 - ²⁵/₁₆₉)] × ¹³/₅
= -[(√(¹⁴⁴/₁₆₉ )] × ¹³/₅
= -¹²/₁₃ × ¹³/₅
= -¹²/₅
tan(arccos (-⁵/₁₃)) = -¹²/₅
The diagram shows the 2nd quadrant of a circle with radius 13, cos a = -⁵/₁₃, and tan a = ¹²/₍₋₅₎ = -¹²/₅.
Answer:
B
Step-by-step explanation:
You cant find the square root of ten. It is a decimal that keeps on repeating. Therefore, it is irrational.