input: What is the answer to this question? the prophet who received the revelation of the qur'an was?

output: Muhammad

input: What is the answer to this question? when do the bride and groom light the unity candle?

output: usually after the formal vows

input: What is the answer to this question? what is the range of visible light in nanometers?

output:
about 390 to 700 nanometers