Answer:
150 million kilometres
Explanation:
The astronomical unit (symbol: au, or AU or AU) is a unit of length, roughly the distance from Earth to the Sun and equal to 150 million kilometres (93 million miles) or 8.3 light minutes.
Humans need a digestive system to do cellular respiration, which produces energy used for growth and movement.
Plants do not need one as they make their own energy through photosynthesis. The process produces glucose, which is a form of energy for the plants.
