What are the students observations and inferences before he starts his investigation

The student has observed that artificial fertilizer makes his plants grow faster and taller than plain soil. He knows that compost is a natural fertilizer. So, he infers that compost will make his plants grow at a faster rate than they grow in plain soil.

answer: tributaries flow into rivers.

wetland is a biome that develops when the water gets accumulated in a land exhibiting a huge depression. these form either seasonally or permanently. the water in the wetland comes from rivers, lakes, ocean, flood, rain or other sources. the wetlands includes mangroves, marshes and peatland.

tributaries flow into the rivers develops a wetland because such water will get deposited in the depression and will restrict the original flow of tributary water. hence, water with low drainage current combines with the river water.