Engine tidak akan bisa berfungsi apabila hanya terdapat system pengapian dan system bahan bakar, Agar bisa berfungsi ditambahkan salah satu factor yaitu:​

While most people who lived in ancient egypt and the middle east avoided settling in nearby deserts, those regions protected them from their enemies. why do you think this was true?

The oldest seafloor in the atlantic ocean is located closest to the edge of the continents. explain how this age can be used to figure out when north america first began to separate from europe

How does sea floor spreading relate to supercontinents?