(i) Yes, plants depend on solar energy to produce food. They require energy from sunlight to perform photosynthesis. If sunlight is not available, they will not be able to make their own food.
(ii) We (humans) are heterotrophic organisms. We obtain nutrition from plant and animal resources. We use plant products as food. All organisms require nutrition, but they use different strategies. Some organisms consume food by breaking down it into smaller parts. Unicellular organisms like Amoeba use pseudopodia to gather food.
(iii) Removal of green cover (deforestation) leads to serious problems. It has a negative impact on our environment and our lives. As we are directly dependent on plants and trees for our food, our survival will be at risk. Deforestation leads to climatic changes. It is a major cause for global warming. Moreover, animals are also badly affected. Their habitats are destroyed.