The answer I got was 3.4 x 10^4 cm per second. To convert 34,000 to scientific notation, I moved the decimal place at the last 0 of 34000 to four places to the left to get from 34000. to 3.4. Whenever you move the decimal to the left, the exponent will be a positive number. I got 10^4 because I move four places to the left.
As a result, I got 3.4 x 10^4 per second. (Please check my method to see if it is correct)
Also, if you move the decimal to the right, the exponent will be negative.