Вставить правильные слова.1) Mountain gorillas live on the steep (slopes)/(sides) of

Воткнуть правильные слова.
1) Mountain gorillas live on the steep (slopes)/(sides) of the rainforest.
2) Environmentalists try to suggest (alternatives)/(possibilities) to cutting down trees to the local people.
3) Tracking gorillas in the rainforest was a vary (easy)/(challenging) experience.
4) He spent the summer working on a conservation (research)(project)