Question: If the cross-section area is 21.2, what is the weight?
Schema: create table table_2071644_2 (weight__kg_m_ varchar, cross_section_area__cm_2__ varchar, PRIMARY KEY (weight__kg_m_))
SQL: select weight__kg_m_ from table_2071644_2 where cross_section_area__cm_2__ = "21.2"