Because sometimes people get different answers because some observe and some actually test and use there senses
Answer:
I think that is called oxalic acid
Explanation:
Answer : The answer in standard form is, 0.00318 mg.
Explanation :
Significant figures : The figures in a number which express the value -the magnitude of a quantity to a specific degree of accuracy is known as significant digits.
The rule apply for the addition and subtraction is :
The least precise number present after the decimal point determines the number of significant figures in the answer.
As we are given :
![(3.26\times10^{-3})mg-(7.88\times 10^{-5})mg](https://tex.z-dn.net/?f=%283.26%5Ctimes10%5E%7B-3%7D%29mg-%287.88%5Ctimes%2010%5E%7B-5%7D%29mg)
First we have to convert scientific notation into standard form.
![\Rightarrow 0.00326mg-0.0000788mg](https://tex.z-dn.net/?f=%5CRightarrow%200.00326mg-0.0000788mg)
![\Rightarrow 0.00318mg](https://tex.z-dn.net/?f=%5CRightarrow%200.00318mg)
As per rule, the least precise number present after the decimal point is 5. So, the answer will be, 0.00318 mg.