Modelling and simulation systems are used in situations where a  ?????  is required, or as learning tools.

Many businesses use a  ?????  to model the way their business works.

 ?????  create models for different investment schemes and performs simulations.

Car manufacturers use the  ?????  to simulate car crashes.

Simulators are  ?????  used for training and in experiments to simulate movement, flight or some other condition.

Drilling simulators are used to  ?????  operators on the drilling rig floor.

Astronauts are trained using a  ?????  which is a model of the shuttle.

Models of  ?????  have led to the discovery of chemical compounds.

Astronomers have used a  ?????  to find the position of stars that could not be seen from earth.

A  ?????v  of a black hole has been used by scientists to simulate its flow of gases.