An apparatus for redundancy of a memory array includes a primary memory array including a plurality of memory cells, one or more of which are defective. The hand-holdable marking tool may be a hand-holdable door marking tool used against a door frame. Methods for producing a maize plant containing in its genetic material one or more traits introgressed into PHEED through backcross conversion andor transformation, and to the maize seed, plant and plant part produced thereby.