Table: election_polls_2011
Columns: polling_firm
date_of_polling
link
progressive_conservative
liberal
new_democratic

Question: How many figures are given for the New Democratic for the polling range May 11–31, 2010?
SQL: SELECT COUNT("new_democratic") FROM election_polls_2011 WHERE "date_of_polling" = 'May 11–31, 2010'

Question: What format is the link for the polling data for February 10–28, 2011?
SQL: SELECT "link" FROM election_polls_2011 WHERE "date_of_polling" = 'February 10–28, 2011'