Arithmetic Operator Puzzles

#1873: 4 _ 5 _ 4 _ 3 = 15 easy #1874: 4 _ 5 _ 6 _ 2 = 19 hard #1875: 4 _ 5 _ 6 _ 3 = 14 medium #1876: 4 _ 5 _ 6 _ 3 = -6 easy #1877: 4 _ 5 _ 6 _ 6 = 19 hard #1878: 4 _ 5 _ 6 _ 8 = 15 medium #1879: 4 _ 5 _ 6 _ 3 = 10 easy #1880: 4 _ 5 _ 7 _ 7 = 19 hard #1881: 4 _ 5 _ 8 _ 4 = 14 hard #1882: 4 _ 5 _ 8 _ 4 = -6 medium #1883: 4 _ 5 _ 8 _ 2 = 16 hard #1884: 4 _ 5 _ 8 _ 4 = 18 hard #1885: 4 _ 5 _ 8 _ 8 = 19 hard #1886: 4 _ 5 _ 8 _ 4 = 10 easy #1887: 4 _ 5 _ 8 _ 6 = 15 medium #1888: 4 _ 5 _ 9 _ 3 = 19 hard #1889: 4 _ 5 _ 9 _ 3 = 17 hard #1890: 4 _ 5 _ 9 _ 9 = 19 hard #1891: 4 _ 6 _ 2 _ 3 = 8 easy #1892: 4 _ 6 _ 2 _ 4 = 7 easy #1893: 4 _ 6 _ 2 _ 5 = 19 hard #1894: 4 _ 6 _ 2 _ 4 = 1 easy #1895: 4 _ 6 _ 2 _ 8 = 6 easy #1896: 4 _ 6 _ 2 _ 9 = 12 medium #1897: 4 _ 6 _ 2 _ 3 = 1 easy #1898: 4 _ 6 _ 3 _ 2 = 13 medium #1899: 4 _ 6 _ 3 _ 9 = 6 medium #1900: 4 _ 6 _ 3 _ 5 = 14 medium #1901: 4 _ 6 _ 3 _ 7 = 18 hard #1902: 4 _ 6 _ 3 _ 8 = 20 hard #1903: 4 _ 6 _ 3 _ 2 = -5 easy #1904: 4 _ 6 _ 3 _ 4 = -4 easy #1905: 4 _ 6 _ 3 _ 5 = -6 easy #1906: 4 _ 6 _ 3 _ 9 = 8 easy #1907: 4 _ 6 _ 3 _ 1 = 9 easy #1908: 4 _ 6 _ 3 _ 2 = 10 easy #1909: 4 _ 6 _ 3 _ 2 = 6 easy #1910: 4 _ 6 _ 3 _ 4 = 4 easy #1911: 4 _ 6 _ 3 _ 5 = 3 easy #1912: 4 _ 6 _ 3 _ 6 = 14 medium #1913: 4 _ 6 _ 3 _ 6 = 2 easy #1914: 4 _ 6 _ 3 _ 7 = 1 easy #1915: 4 _ 6 _ 3 _ 8 = 1 easy #1916: 4 _ 6 _ 3 _ 9 = 17 hard #1917: 4 _ 6 _ 3 _ 9 = -1 easy #1918: 4 _ 6 _ 3 _ 2 = 1 easy #1919: 4 _ 6 _ 3 _ 3 = 6 easy #1920: 4 _ 6 _ 3 _ 4 = 8 easy