The formula is B2O3. The charges need to equal each other to obtain a neutral compound of no charge hence 2 B has a charge of +6 and 3 O has a charge of -6 to cancel out each other, resulting in a stable uncharged compound.
Answer:
Your missing the entire Transitional Metal group as well as all the Lanthanides and Actinides.
Explanation:
The groups are:
Alkali metals.
Alkaline earth metals.
Transitional metals.
Crystallogens.
Pnictogens.
Chalcogens.
Halogens.
Noble gases.
Answer:
Balanced reaction: 
The mole ratio (4 moles Zn/5 moles 
) is correct.
Explanation:
Oxidation: 
Balance N and O: 
Balance charge: 
................(1)
Reduction: 
Balance N: 
Balance H and O: 
Balance charge: 
............. (2)
[
Equation-(1)] + [Equation-(2)]:
So, balanced reaction:
Hence the mole ratio (4 moles Zn/5 moles ) is correct.
Answer:
B. Can it be completed within 120 days?
C. Will it cost less than $10,000?
Explanation:
''Can it be completed within 120 days?'' and ''Will it cost less than $10,000?'' are the two questions that can be used to identify time and cost constraints in the design. The first question ask about the time that the machine needs to complete the work while on the other hand, the second question ask about the cost needed by the machine for completing the action.
