Question

Twenty-five years ago 16 billion tonnes of carbon dioxide (Co2),the gas which causes the 'greenhouse effect' ,(release) ....into the air by motor vehicles and industry in a year.
Fish
In 1974 56 million tonnes of fish(take) ...from the earth's oceans.
Since then the number of fish taken from the oceans (rise) ...to 90 million tonnes a year.
Endangered species
In 1975 there were two million African elephants.This year the number of African elephants (fall)...to 500,000.
Rainforests
Twenty-five years ago 100,000 sq. km of the earth's rain forests(lose)...each year.
Population
In 1974 the earth's population was 3.84 billion.The earth's populations is now over 6 billion.Each year it (rise)...by 95 million.

Answer 1

were released/were taken/has risen/has fallen/has been lost/has risen

Succes!