I need the answer asap 20 points In an arithmetic sequence, the first term, a_1,a
1 , is equal to 5,5, and the fifth term, a_{5},is equal to 41.41. Which number represents the common difference of the arithmetic sequence?

Which one ? is the answer and how to find this answer

He mass of a single atom of carbon can be found by dividing the atomic mass (12.01 g) by 6.022 x 10^23. which is the mass of a single carbon atom, correctly written in scientific notation with the correct number of significant figures?

Which of the following is not a subset of {1,2,3}?