<span>4[(10-4) 2 to the second power divided by 4]
=4x6x2</span> to the second power divided by 4
=6x2 to the second power
=6x4
=24
Hope that helps and hope that I didn't misunderstand your question
21 divide by 4 is 5.25. She travels 5.25 miles per hour. 42 divide by 5.25 is 8. It would take 8 hours for Shelly to bike 42 miles.