So the answer is 1,024.
If the hash is a good cryptographic hash
and it produces a uniform distribution,
the probability that any bit is a zero is 1/2,
and we need to find an applet that starts with 10 zeros.
Note that it doesn't matter how big the output of the hash function is.
This is the same whether it's a 256-bit output or 192-bit output.
It doesn't matter how big the output of the hash function is,
whether its only outputting 10 bits
or its outputting a more reasonable number, like 256 bits,
as long as we restrict it to the first 10 bits having to be zero.
