Arithmetic Operator Puzzles

#433: 1 _ 8 _ 9 _ 4 = 19 hard #434: 1 _ 8 _ 9 _ 6 = 13 hard #435: 1 _ 8 _ 9 _ 3 = 11 hard #436: 1 _ 8 _ 9 _ 9 = 7 medium #437: 1 _ 8 _ 9 _ 4 = 18 hard #438: 1 _ 9 _ 2 _ 3 = 7 medium #439: 1 _ 9 _ 2 _ 4 = 19 hard #440: 1 _ 9 _ 2 _ 3 = -5 medium #441: 1 _ 9 _ 2 _ 2 = 8 medium #442: 1 _ 9 _ 2 _ 3 = 6 easy #443: 1 _ 9 _ 2 _ 6 = 3 easy #444: 1 _ 9 _ 3 _ 2 = 7 medium #445: 1 _ 9 _ 3 _ 4 = 13 hard #446: 1 _ 9 _ 3 _ 5 = 16 hard #447: 1 _ 9 _ 3 _ 2 = -5 medium #448: 1 _ 9 _ 3 _ 3 = 8 medium #449: 1 _ 9 _ 3 _ 1 = 2 easy #450: 1 _ 9 _ 3 _ 2 = 1 easy #451: 1 _ 9 _ 3 _ 3 = 6 medium #452: 1 _ 9 _ 3 _ 4 = 7 medium #453: 1 _ 9 _ 3 _ 4 = 12 medium #454: 1 _ 9 _ 3 _ 5 = -2 medium #455: 1 _ 9 _ 3 _ 5 = 15 hard #456: 1 _ 9 _ 3 _ 6 = 9 medium #457: 1 _ 9 _ 3 _ 6 = -3 medium #458: 1 _ 9 _ 3 _ 7 = 10 medium #459: 1 _ 9 _ 3 _ 8 = 11 hard #460: 1 _ 9 _ 3 _ 8 = -5 medium #461: 1 _ 9 _ 3 _ 9 = 12 hard #462: 1 _ 9 _ 3 _ 9 = -6 medium #463: 1 _ 9 _ 3 _ 6 = 2 easy #464: 1 _ 9 _ 4 _ 2 = 19 hard #465: 1 _ 9 _ 4 _ 3 = 13 hard #466: 1 _ 9 _ 4 _ 8 = 19 hard #467: 1 _ 9 _ 4 _ 6 = -5 medium #468: 1 _ 9 _ 4 _ 3 = 12 medium #469: 1 _ 9 _ 4 _ 6 = 6 easy #470: 1 _ 9 _ 4 _ 8 = 18 hard #471: 1 _ 9 _ 5 _ 3 = 16 hard #472: 1 _ 9 _ 5 _ 5 = 8 medium #473: 1 _ 9 _ 5 _ 3 = 15 hard #474: 1 _ 9 _ 6 _ 8 = 13 hard #475: 1 _ 9 _ 6 _ 4 = -5 medium #476: 1 _ 9 _ 6 _ 2 = 12 hard #477: 1 _ 9 _ 6 _ 3 = 11 hard #478: 1 _ 9 _ 6 _ 6 = 8 medium #479: 1 _ 9 _ 6 _ 2 = 3 easy #480: 1 _ 9 _ 6 _ 4 = 6 easy