A component to something means a part or piece.
Humus is the organic compound in soil/earth
Qualitative data is specific data you record about something that has to do with the physical features of that item. Say you look at a pencil. That pencil is yellow. It is not sharpened. Something like that
Quantitative data is data that has to do with numbers. A hexagon has 6 sides. There are 3 birds in that tree. That pen has two different colors.
A hypothesis is an educated guess about something
Justify means to explain/prove a point that you are making. If you say something like ice melts faster in hot water vs cold water, you would justify it by testing ice in hot and cold water, and recording the results.
I hope this helps :)