You are presented with the quiz "Powering what with a battery requires a path for electricity to flow?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "powering an electrical device with a battery requires a path for electricity to flow through a closed circuit" and "today's cellular phones are second-generation devices". So, what's the best answer to the question?
OPTIONS:
- closed
- energy
- complete
- vehicles
- engines
- a phone
- buses
- Cars

Answer: a phone

You are presented with the quiz "What is used as an energy source by television?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "electricity is used as an energy source by electrical devices" and "electrical fields result from electrical devices and televisions". So, what's the best answer to the question?
OPTIONS:
- electricity
- light
- our nearest star
- air
- energy
- satellites
- photons
- rocks

Answer: electricity

You are presented with the quiz "What part of a tree would be woody and covered in bark?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "trees have woody stems covered with bark" and "stems of plants include trunks and branches". So, what's the best answer to the question?
OPTIONS:
- shrub beds
- the leaves
- the roots
- cacti
- a sapling
- Chlorophyll
- the trunk
- four limbs

Answer:
the trunk