Teachers are categorized in four main classes in Bangladesh at University level. The ascending rank of teacher is Lecturer, Assistant Professor, Associate Professor and Professor. The initial position Lecturer is generally enrolled as the top student of the class. Master's degree is required for normal university level Lecturer.
Humus soil is soil made up of decayed organic material. Popularly, it refers to soil that is light in texture, dark brown or black in color, and sweet-smelling.
Bedrock is the solid layer of rock beneath the soil. Soil is a mixture of rock particles, minerals, decayed organic material, air, and water. The decayed organic material in soil is humus, a dark-colored. substance that forms as plant and animal remains decay. Humus helps create. spaces in soil for air and water that plants must have.