What is 71,000,000 converted to scientific notation? A. 71 x 100,000
B. 7.1 x 100,000
C. 7.1 x 10-7
D. 7.1 x 107

 D)  

Explanation:

Place the decimal point between the first two digits of the given number. Erase everything after the '1'. So we have 7.1

To get back to 71,000,000 we would need to move the decimal point 7 spaces to the right

So that's why

If the exponent was -7, then we would move the decimal point 7 spaces to the left.