What is the weight of the shell that reached its maximum height at 40° in 12.6 seconds?
CREATE TABLE "performance" (
  "m_v_ft_s" real,
  "shell_lb" real,
  "time_to_ft_m_at_25_seconds" text,
  "time_to_ft_m_at_40_seconds" real,
  "time_to_ft_m_at_55_seconds" real,
  "max_height_ft" real
);
SELECT "shell_lb" FROM "performance" WHERE "time_to_ft_m_at_40_seconds"=12.6;