Question 43604
log10000 means "the power of 10 that gives you the number 10000"
That power is 4.  So log10000=4.

The conversion formula for logarithms is:

log(base a)b = [log(base c)b]/[log(base c]a]

So log(base 2)10 = log(10)/log(2) = 1/log(2)

Cheers,
Stan H.