1) Вы уверены что uvailable правильно написано, возможно вы имели available?
тогда вот мой вариант: It's all available scenarios
2) A couple of decades ago Africans small unequal rights.
3) It unimportant, it is better to pay attention to more pressing problems.
4) These lands are unsuitable for life.
5) Our situation is unsatisfactory, you should immediately improve the situation.