<human>: Does the sentence "Another example is Ali Qushji -an astronomer, mathematician and physicist originally from Samarkand- who became a professor in two madrasas, and influenced Ottoman circles as a result of his writings and the activities of his students, even though he only spent two or three years before his death in Istanbul." provide a valid answer to the question "How many years did Ali Qushji spend in Istanbul?"
OPTIONS:
- yes
- no
<bot>: yes