CREATE TABLE table_46803 ("Engine type" TEXT, "Scenario" TEXT, "SFC in lb/ ( lbf\\u00b7h ) " FLOAT, "SFC in g/ ( kN\\u00b7s ) " FLOAT, "Specific impulse  ( s ) " FLOAT, "Effective exhaust velocity  ( m/s ) " FLOAT)

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 4,423
SELECT AVG("Specific impulse (s)") FROM table_46803 WHERE "SFC in lb/(lbf\u00b7h)" = '7.95' AND "Effective exhaust velocity (m/s)" > '4,423'
SELECT AVG("Specific impulse (s)") FROM "table_46803" WHERE "Effective exhaust velocity (m/s)" > '4,423' AND "SFC in lb/(lbf\u00b7h)" = '7.95'