Review the tweet "Africa has unique and tremendous problems with war, overpopulation, starvation and tribalism which makes moving Africa forward hard." and assign it to one of the emotional state categories. The categories are: 3: very positive emotional state can be inferred, 2: moderately positive emotional state can be inferred, 1: slightly positive emotional state can be inferred, 0: neutral or mixed emotional state can be inferred, -1: slightly negative emotional state can be inferred, -2: moderately negative emotional state can be inferred, -3: very negative emotional state can be inferred.