Question: What is the average SFC in lb/(lbf·h) for engines with an Effective exhaust velocity (m/s) larger than 29553, and a SFC in g/(kN·s) of 17.1?
SQL: SELECT AVG("SFC in lb/(lbf·h)") FROM "2-15944-5" WHERE "Effective exhaust velocity (m/s)" > 29553.0 AND "SFC in g/(kN·s)" = 17.1;

Question: What is the specific impulse for the engine with a scenario of SR-71 at Mach 3.2 (Wet)?
SQL: SELECT "Specific impulse (s)" FROM "2-15944-5" WHERE "Scenario" = 'SR-71 at Mach 3.2 (Wet)';

Question: what is the average specific impulse for engines that have a SFC in lb/(lbf·h) of 7.95, and a Effective exhaust velocity (m/s) larger than 4423
SQL: SELECT AVG("Specific impulse (s)") FROM "2-15944-5" WHERE "SFC in lb/(lbf·h)" = 7.95 AND "Effective exhaust velocity (m/s)" > 4423.0;