Greenworks 10-Inch Mower Blade Replacement Set 29712

Does the blade come sharp?

dOES THIS BLADE FITS ON tASK fORCE 18 in electric lawn mover, at lowes got similar blade Task Force 18-in Standard Mower Blades

Will this blade fit on the Kobalt 80 volt mower with a 21 inch blade

Will this blade work for model 25213 that has a 21" deck?