Option c : 9 is the answer.
Explanation:
The expression is 
We need to determine the subtracted value of the expression.
From the expression we can see that the expression contains two negative signs.
To simplify the expression, we know that, When we multiply two negative numbers then the product is always positive.
This means 
Thus, the expression can be written as

Adding the two numbers, we get,

Thus, the value of the expression is 9.
Hence, Option c is the correct answer.
Answer:
10%
Step-by-step explanation:
The molar mass of N2O5 (Dinitrogen pentoxide) is 108.01 g/mol.
Answer: 64 centimeters squared.
Step-by-step explanation: This shape is a parallelogram. And the area of a parallelogram is just the base multiplied by the height. Here, the base is 10 cm and the height is 7 cm. So you might think the the area is just 70 centimeters squared. But here's the catch. There is a rectangular region in this parallelogram that is not shaded. But you can still easily solve this problem. All you need to do is find the area of that rectangular region and you already know the length and the width of this region. And, remember, the area of a rectangle is just the length and the width multiplied. So here, the area of that rectangular region is just 2 cm multiplied by 3 cm. Which will give you 6 centimeters squared. Now, all that's left to do is subtract the area of that rectangular region, 6 centimeters squared, from the total area of the parallelogram, 70 centimeters squared. And that should give you 64 centimeters squared as your final answer. I really hope this makes sense and is helpful.