My opinion, second option for 1 is right since
that refers to
substances and not
sulphur. Hence the verb must be plural - hence
that burn is right
For the Da Vinci painting, I think the sentense is wrong because of the tense
which is damaged. The simple present tense in
is means something was not true in the past, but is true today - a change that is current. The current answer should be
Quote:
The Painting of Da-Vinci, which was damaged, has raised $3m on the first day of the Auction.