question:
Many wet-chemical tests for copper ions exist, one involving potassium ferrocyanide, which gives a brown precipitate with copper(II) salts.
What are copper salts used to test?

answer: no

question:
The network consists of six lines with a total length of 189.63 kilometres (117.83 miles) with 142 stations, of which 35 are underground, five are at-grade, and the remainder are elevated.
How many of the New Delhi Metro's stations are located at ground level?

answer: yes

question:
In 1919, following the Treaty of Versailles, the city was restituted to France in accordance with U.S. President Woodrow Wilson's "Fourteen Points" without a referendum.
What year was it restituted to France?

answer: yes

question:
He claimed to have observed Venus as a spot on the Sun.
Where did Avicenna think Venus was in relation to the sun?

answer:
no