Depends on the music. The most popular ones include timpani, triangle, cymbals, snare drum, bass drum
Not sure who helped make painting on canvas a common practice but around the end of the 15th century, canvas<span> became more popular as it was cheaper, easier to transport, allowed larger works, and did not require complicated preliminary layers of </span>gesso.
Contours are lines on a map that show or represent the height of the land. When contours are closely spaced this means that the land rises rapidly with distance or the land is steep. When they a widely spaced it means the land rises gently or the area is relatively flat or undulating. Specific contour shapes usually represent a particular land form or feature. V shaped contours usually represent a valley or a river valley.