What organ system in the human body contains the pituitary gland, hypothalamus gland, and thyroid gland?
A: endocrine system

In the initial stages of manned space exploration, scientists needed to address adequate nutrition to provide astronauts with energy throughout the mission. Which of these criteria could not be used when considering food and energy for astronauts during manned space flights?
A: history of space food

Mark wants to make lemonade for his friends. He uses water, lemon juice, and sugar. Which of these best describes the lemonade?
A: a mixture

Which object best reflects light?
A:
white floor