Read the given passage and answer the questions that follow:

Impressionism was a radical art movement that began in the late 1800s, centred primarily around Parisian painters. Impressionists rebelled against classical subject matter and embraced modernity, desiring to create works that reflected the world in which they lived. Uniting them was a focus on how light could define a moment in time, with colour providing definition instead of black lines. 

The Impressionists emphasised the practice of plein-air painting or painting outside. Initially derided by critics, Impressionism has since been embraced as one of the most popular and influential art styles in Western history.

Impressionism coalesced in the 1860s when a group of painters including Claude Monet, Alfred Sisley and Pierre-Auguste Renoir pursued plein-air painting together. American John Rand never joined their ranks as a preeminent artist, but as a painter living in London, he designed in 1841 a device that would revolutionize the art world: paint in a tube. His clever new technology offered easily portable, pre-mixed paint, and allowed painters to bring their process outdoors.