The answer is 1
I'm not sure what letter though because you wrote both a and c as 1
Here is a good way to think about it
[tex] 10^{4} =10000[/tex]
[tex] 10^{3} =1000[/tex]
[tex] 10^{2} =100[/tex]
[tex] 10^{1} =10[/tex]
[tex] 10^{0} =1[/tex]
[tex] 10^{-1} =.1[/tex]
[tex] 10^{-2} =0.01[/tex]
[tex] 10^{-3} =0.001[/tex]
[tex] 10^{-4} =0.0001[/tex]
