I found -2−2 but I considered base 1010 for your log.
Explanation:
I assume a log in base 1010 so you have: log_(10)(sqrt(0.0001))=log_(10)(1/10000)^(1/2)=1/2[log_(10)(1)-log_(10)(10000)]=1/2[0-4]=-2log10(√0.0001)=log10(110000)12=12[log10(1)−log10(10000)]=12[0−4]=−2