Answer:
A. air pressure,this is answer.
A single fixed pulley is used to lift load by changing the direction of the lifting force. Even though a single fixed pulley has no mechanical gain in that, the effort applied is greater than the load, it is preferred in use since you do not have to pull or push the pulley up and down.
The endocrine system is important to the function of the human body because, endocrine glands release hormones into the bloodstream. Which lets the hormones travel to the cells in other parts of the body. This also helps control mood, growth and development, the way our organs work, metabolism and reproduction.
The segment that represents melting is time (minutes) and temperature.