What is the volume of a sphere whose radius is 16.9?

(4 pi r^3) / 3

4 times 16.9 = 67.6 ( step 1 )
67.6^3 = 308915.776 ( step 2 )
308915.776 / 3 ( step 3 )
 
The answer before pi is ( 102971.925333 * PI ^3  )      ( step 4 )
after PI is ( 323495.844152 ^ 3 )

i first multiplied the radius by 4 (step 1)
i then cubed the number from step 1 ( step 2 )
i divided the number from step two by three ( step 3)
i then multiplied by PI, but also gave an answer without multiplying ( step 4 )