A vaccine uses a live pathogen that is too weak to make you sick. Once it enters your body you defeat it easily. Now that yur body is familiar with it your body can fight off the disease in the future.
<span>c. regular exercise has little impact on maintaining peak performance after age 30</span>
Conservationists occasionally light forests on fire to control wild fires. By occasionally burning material (like leaves, branches, etc), those materials cannot build up and cause large and uncontrollable fires later.
Answer: High Frequency waves by method of compression bone conduction
Explanation: in this, vibration of the bones of the skull and sometimes, arguably soft tissues leads to the production of sounds. The outer and middle ear is bypassed in this method of sound production. Sound reaches the inner ear directly and its a process largely involved in designing hearing aids.
the excretory system. the kidney produce more concentrated urine so less water is lost from the body. sweat help maintain your body's natural temperature.