Which statement describes a scientific theory?

A theory states how something behaves without explaining why.
A theory is a proven fact that cannot be changed.
A theory changes based on new observations and testing.
A theory is based on a single hypothesis or observation.

A theory changes based on new observations and testing.

Explanation:

Multiple observations and repeated trials results in the formulation of scientific theory.

The scientific theory is one of the methods used in science to explain a particular observation. They are usually ascertained from carrying out multiple trials and experiments to validate a claim.

A scientific theory simply provides an explanation into a phenomenon. A law just states how something behaves.

weather forecasts are done by collecting data about the current state of the atmosphere mainly the temperature, humidity and wind and using meteorology, to determine the atmosphere that evolves over time. the h and l mean the high and low pressure. the red strip is a warm front. the blue strip is a cold front. the blue and red strip is a stationary front. the purple strip is a occluded front.

explanation:

conservation of mass

mass before something happens = mass afterwards