2. Coins vs qubits
Basic ProbabilityA fair coin is flipped 10 times. Let's call $p$ the probability that all the coin flips turn heads. Now, consider a qubit in an equal superposition state $(|0\rangle + |1\rangle)/\sqrt{2}$ which is being measured 10 times without preparation. Let's call $q$ the probability that all the measurements result in $|0\rangle$. What is the ratio $p/q$?
Hint
Think about what happens if a qubit is measured, and then measured again without preparing the same initial state.