CREATE TABLE table_79055 ("Name or route" TEXT, "type" TEXT, "elevation groundstation" FLOAT, "elevation mountainstation" FLOAT, "slope length" FLOAT, "capacity in persons/hour" FLOAT, "construction year ( s ) " TEXT)

Which elevation groundstation has a capacity in persons/hour larger than 820, and a Name or route of lager 1, and a slope length smaller than 336?
SELECT AVG("elevation groundstation") FROM table_79055 WHERE "capacity in persons/hour" > '820' AND "Name or route" = 'lager 1' AND "slope length" < '336'
SELECT AVG("elevation groundstation") FROM "table_79055" WHERE "Name or route" = 'lager 1' AND "capacity in persons/hour" > '820' AND "slope length" < '336'