Answer:
[tex] {8}^{13} [/tex]
Step-by-step explanation:
[tex] {8}^{4} \times {8}^{9} \\ {8}^{4 + 9} \\ {8}^{13} \\ = 5.497558139 \times 10 ^{11} [/tex]
Hope this helps you.
Let me know if you have any other questions :-)