CREATE TABLE table_78426 ("Driver" TEXT, "Constructor" TEXT, "Laps" FLOAT, "Time/Retired" TEXT, "Grid" FLOAT)

What is the total number of grids for peter gethin?
SELECT SUM("Grid") FROM table_78426 WHERE "Driver" = 'peter gethin'
SELECT SUM("Grid") FROM "table_78426" WHERE "Driver" = 'peter gethin'