Question: How much was spent on public safety by the Town of Cary in 2010?
SPARQL:
 select sum(xsd:decimal(?amount)) as ?result from <http://linkedspending.aksw.org/town_of_cary_expenditures> { ?obs qb:dataSet ls:town_of_cary_expenditures. ?obs lso:town_of_cary_expenditures-amount ?amount. ?obs lso:town_of_cary_expenditures-Class <https://openspending.org/town_of_cary_expenditures/Class/4>. ?obs lso:refYear ?year. filter(year(?year)=2010). }