In which of the following reactions is Magnesium required as an activator?

Magnesium is the activator of many enzymes requiring ATP. The enzymes requiring magnesium are alkaline phosphates, hexokinase, fructokinase, phosphofructokinase, phosphopyruvic and acetyl trans phosphorylases. It is also required for the activation of adenyl cyclase systems and for the activity of cyclic AMP dependent kinases like those involved in phosphorylation of nucleotides and glycogen metabolism. Ref: Textbook of Biochemistry and Human Biology By L. M. Srivastava, 3rd Edition, Page 583 ; Textbook of Biochemistry By D M Vasudevan, 3rd Edition, Pages 288-9