input: OPTIONS:
- synovial fluid
- phloem
- bile
- mucous Now, answer this question: Q: What does the esophagus produce for lubrication? A:
A:
output: mucous

Q: What is the smallest particle of an element that still has the properties of that element is called? A:

OPTIONS:
- nucleus
- neutron
- proton
- atom

Answer: atom

Problem: OPTIONS:
- secondary
- liquid
- carbon
- primary
Q: Q: What type of pollutants enter the air directly? A:
Answer: primary

Problem:OPTIONS:
- a carbon
- a hydrogen
- a cobalt
- an alloy

Q: A mixture of a metal with one or more other elements is called? A:
****
A: an alloy

Q: Isothermal expansion is a process occurring without a change in? A:
OPTIONS:
- weight
- variation
- precipitation
- temperature
temperature

Q: Light waves which interfere with themselves after interaction with a small aperture or target are said to what? A:
OPTIONS:
- refract
- adduce
- reflect
- diffract

Answer:
diffract