Well, for the trivial questions:
1. The cor anglais, while literally meaning the 'English horn' is neither english OR a horn. Alledgedly, the instrument's current name derives from a time when it more closely resembled an oboe da caccia, an instrument from the baroque period in the alto voice. As the oboe da caccia was curved or bent, the original term was cor anglé or BENT horn, which years of abuse at the hands of the English corrupted into 'cor anglais' or 'English horn'.
2. The quack of a duck does not echo.