Use of which of the following does not contribute carbon dioxide to the environment
(1. refrigarator
(2. charcole grill
(3.computer
(4.bicycle

Choices 1, 2, and 3 all emit carbon dioxide, not enough to destroy the planet, but they still can cause it over a large amount of time, due to Carbon Dioxide being a greenhouse gas. Therefore, the answer is 4. Bicycles do NOT emit any carbon dioxide at all.

A dog is a multicellular organism. It obtains energy from the food it eats and uses this energy to perform its vital life functions. A dog eliminates waste through panting, feces, urine, and respiration. It has a definite boundary, as its inner organs are covered by skin and fur. A dog regulates homeostasis in different ways. One way is by panting, which helps the dog maintain a stable internal temperature. Like humans, a dog has a complex organ system that grows and develops throughout its entire life. A dog reproduces and passes on genetic information to its puppies. It also senses and responds to stimuli. For example, a dog has a very astute sense of smell, and its mouth waters when it smells food.