Answer:
5×10⁵
5×10⁶
Step-by-step explanation:
1)
[tex]\dfrac{4\cdot 10^{15}}{8\cdot 10^{9}}=\dfrac{40\cdot 10^{14}}{8\cdot 10^{9}}\\\\=\dfrac{40}{8}\cdot 10^{(14-9)}=5\cdot 10^{5}[/tex]
2)
[tex]\dfrac{2\cdot 10^{-5}}{4\cdot 10^{-12}}=\dfrac{20\cdot 10^{-6}}{4\cdot 10^{-12}}\\\\=\dfrac{20}{4}\cdot 10^{(-6-(-12))}=5\cdot 10^{6}[/tex]