input question: What is the missing first step of the following process: - The blood is passed through the nephrons in the kidneys - The kidneys filter the waste from the blood - The clean blood is circulated out of the kidneys - Excess water and waste is expelled from the kidneys in the form of urine.???
output answer: The kidneys receive blood through the renal artery

input question: What is the missing first step of the following process: - Ocean water pulls sand off of beaches - Ocean water breaks rocks off of cliffs - Ocean water carries sand and rocks into the ocean - Sand and rocks go to other land or the bottom of the ocean.???
output answer: Ocean waves hit land

input question: What is the missing first step of the following process: - The star burns until it runs out of fuel - The star can no longer support its weight - The layers of hydrogen press down on the core - The core gets smaller and smaller under the pressure - The pressure causes gravity to get stronger - The gravity becomes so powerful that nothing can escape it - Anything that gets close to it, is drawn into it by its gravity - Light is drawn into it - Light can not escape -???
output answer: Stars burn mass

input question: What is the missing first step of the following process: - The plants and floor absorb the the sunlight - The absorbed sunlight is converted to heat - The heat cannot escape the glass - The heat is trapped in the greenhouse - The hot air rises - The colder air at the top is pushed to the bottom - The colder air is then warmed by the floor and the plants.???
output answer:
Sunlight passes through the glass into the greenhouse