Which one of the following ecosystem type has the highest annual net primary productivity?

Water vapour is:

A. A gas

B. A cloud droplet

C. A rain drop

D. A snowflake

What is the cause of the Exxon Valdez?

A. Oil Tanker which sank in 1989 along the coast of Alaska and marine life seriously affected.

B. a plane which crashed and caused death of human life

C. a ship which wrecked on the coast of India

D. none of these.

In calm air the air temperature is -10^o C, if the wind speed should increase to 30 knots (with no change in air temperature) the thermometer would indicate:

A. A much higher temperature than -10^o C

B. A much lower temperature than -10^o C

C. A temperature of -10^o C

D. A temperature of -30^o C

Infrared and visible satellite images might provide:

A. A way of determining cloud thickness and altitude.

B. A way of distinguishing between wet and dry clouds.

C. A way of identifying clouds suitable for cloud seeding.

D. A way of distinguishing between "new" and "old" clouds.