In miles 365 million miles or 365,000,000
in km, 588 million km or 588,000,000
so
scientific notation=(number less than 10 and greater than or equal to 1) times 10^n
so
we need to move the decimal point 8 spaces to the left
to compensiate for that, we multiply by 10⁸ which will move it 8 to the right
so
365,000,000 mi=3.65 times 10⁸ mi
588,000,000 km=5.88 times 10⁸ km
those are the distances in scientific notation
9,2.5,-4,-10.5,-17
Let's find the difference between two consecutive terms
2.5 - 9 = -6.5
-4 - 2.5 = -6.5
-10.5 - (-4) = -6.5
-17 -(-10.5) = -6.5
We can see that the common difference is -6.5
-6.5 is the common difference between successive terms in the sequence 9,2.5,-4,-10.5,-17
the common difference is negative because we subtract 6.5 to get the next term.
21 students
You find this by subtracting the number of students absent from the total amount of students in the class 
.
