SELECT "PAL M" FROM table_44198 WHERE "PAL I" = '50hz'
Which PAL M has a PAL I of 50HZ?
CREATE TABLE table_44198 (
    "NTSC M" text,
    "PAL B,G,H" text,
    "PAL I" text,
    "PAL N" text,
    "PAL M" text
)