error of calculated resonance frequency?

hey guys, i've been struggling with this one for a while =/

and also, my friend told me the Inductance value for Execution sheet #3 should be in the lab manual, but I don't see it o.o

if you guys could help me out, i would greatly appreciate that thanks

This was on the exam. It's (.5)*{sqrt((sum of the two relative errors)^2)}