*Question*
Q: The contents of which organ are mixed every 20 seconds? Choices: - the metabolism - pancreas - kidney - the stomach A:
**Answer**
the stomach

*Question*
Q: Early in the development of a human fetus, the skeleton is made entirely of what? Choices: - bones - anterior - membrane - cartilage A:
**Answer**
cartilage

*Question*
Q: What is the area where an electron is most likely to be found called? Choices: - neutron - proton - neucleus - orbital A:
**Answer**
orbital

*Question*
Q: What explains why water molecules tend to stick together? Choices: - helium bonds - covalent bonds - mineral bonds - hydrogen bonds A:
**Answer**
hydrogen bonds