Table schema:
CREATE TABLE table_name_62 (prom__m_ INTEGER, height__m_ VARCHAR, class VARCHAR, peak VARCHAR)

Question: Tell me the lowest prom for class of hewitt and peak of cushat law and height more than 615
SQL: SELECT MIN(prom__m_) FROM table_name_62 WHERE class = "hewitt" AND peak = "cushat law" AND height__m_ > 615