The correct answer is c. smoke stacks.
Smoke stacks are chimneys or funnel shaped structures which emit smoke from a factory, vehicles and industrial set ups. Smoke stacks mostly discharge carbon dioxide and water vapor and oxides of nitrogen into the atmosphere. The exhaust released from smoke stacks cause air pollution. Air pollution can cause ailments like asthma and cancer. Thus, smoke stacks are not a source of water pollution.
This procedure is called In Vitro Fertilization (IVF)
Hi,
The answer should be letter B, as H2O is a compound made of two different elements in a definite proportion.
Answer:
About 5billion years ago is the correct option.
Explanation:
Hope this will help you :)
