Answer: the lowest note that would be possible to blow on this brass pipe is approximately 1700 Hz
Explanation: f = c / (2L)
where c is the speed of sound in brass, which is around 340 m/s.
Changing over the length of the pipe to meters, we have:
L = 10 cm = 0.1 m
Stopping within the values, we get:
f = 340 / (2 x 0.1) = 1700 Hz