By Earth history standards, the Grand Canyon is . not important as old as the Earth very old young becoming a first-order landform

d. new methods of assembly are introduced.

explanation:

this allows for the goods to be made on a larger scale. not faster because now it is shown to be made better, hence the greater productivity in the question. it is calling for something new to be introduced.

seismic wave -

an elastic wave in the earth produced by an earthquake or other means.

explanation:

answer called a epicycle;