Answer:
[tex]2.25\times 10^{-17}[/tex]
Step-by-step explanation:
[tex](2.5\times 10^{-8})(9\times 10^{-10})=(2.5\times 9)\times 10^{-8-10}\\\\=22.5\times 10^{-18}\\\\=2.25\times 10^{-17}[/tex]
