Answer:
Precise but not accurate.
Explanation:
We can tell the performance of the balance is precise, because the repeated measurements give values close to one another.
However, the performance of the balance is not accurate, as the mean value of the repeated measurements (195.587) is not close to the value considered as true (in this case the standard calibration mass with a certified value of 200.002 g).
Answer:
The correct answer is: X is nitrogen dioxide, and Y is a metal oxide
Explanation:
Combustion of compound of containing nitrogen and metal will give nitrogen dioxide and metal oxide as product. During combustion reaction a compound reacts with oxygen in order to yield oxides of elements present in the compound.
The general equation is given as:

Hence, the correct answer is :X is nitrogen dioxide, and Y is a metal oxide.
Presuming the arrow is between H20 and CO
On the left there are 2 gas moles.
On the right there are 4 gas moles.
The equilibrium will shift to the side with the most no. He gas moles when pressure is decreased.
Therefore the answer is A, since 4>2.
If you have any questions, feel free to ask