How many knots did the Ms Moby Vincent have when passengers was less than 1.6?
CREATE TABLE "current_fleet" (
  "ship" text,
  "built" real,
  "entered_service" real,
  "route" text,
  "gross_tonnage" text,
  "length" text,
  "width" text,
  "passengers" real,
  "vessels" real,
  "knots" real
);
SELECT COUNT("knots") FROM "current_fleet" WHERE "ship"='ms moby vincent' AND "passengers"<1.6;