Human Environment

Which of the following statements is correct? I. Montreal Protocol was signed in 1987. II. Earth Summit 1992 was held at Rio-de-Janeiro. III. World Environment Day is 5 June. IV. World Environment Day coincides with commemoration of First United Nations Conference of Human Environment. V. At DO below 4 mg/L water at normal temperature is heavily polluted.

Differentiate between Physical Environment and Cultural Environment.

Natural Environment

Which are different adverse effect of biotechnology on human health and environment?