How many molecules of adenosine triphosphate has the cell invested by the end of the fifth step of glycolysis?

1. Step one spends one adenosine triphosphate when hexokinase phosphorylates glucose. 2. Step three spends a second one when phosphofructokinase adds another phosphate. 3. At the end of the fifth step there is a net investment of energy from two such molecules per glucose. 4. No further investment is needed, because the sixth step adds its phosphate without spending any. _Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 7 "Cellular Respiration", section 7.2 Glycolysis_