Through the metric system
The answer would be 6b-3c because a would cancel out and be 0
Step-by-step explanation:

Hello!
I would say the second option, because it looks like the most reasonable one. The third and fourth options decrease, but we can see by the chart that in fact, the weight increases. Also, it wouldn't be the first option, because its showing that the wight is always constant and rate doesn't change. However, we can see that this is wrong and the rate actually does change. Therefore, the second option looks like the most reasonable for this chart.
Hope this helps!
Answer:
The result after adding a set of numbers or is called a sum.
Step-by-step explanation:
Consider the provided information.
The four mathematical operations are:

The sign + is used to add numbers.
The sign - is used to subtract the numbers.
The sign × is used for the product of the numbers.
The sign ÷ is used for division of the numbers.
When we add two or more number by using the operator + the obtained number or value is called the sum of the numbers.
For example:
Consider the number: 2 + 5 if we add the number the resulting value will be 7.
The number 7 is the sum of 2 and 5.
Thus, the result after adding a set of numbers is called a sum.