Which invention developed into the power source of the industrial revolution​

The coal-fired steam engine was soon developed. It became the key technology of the Industrial Revolution. In preindustrial Europe, water power was widely used as a source of energy. By the late 1700s, however, steam engines had been perfected

some women in the middle and upper classes worked as doctors, government officials, or priestesses. both women and men enjoyed a better quality of life the higher they were on the social pyramid. the egyptians believed that their class system created a stable, well-ordered society. each group had its own role to play.

my friend is on my computer