Which of these statements about neutrons is true?
a. neutrons travel around the nucleus of an atom.
b. a neutron has no charge.
c. neutrons have less mass than electrons.
d. the number of neutrons in an atom always equals the number of electrons.

answer: - few nutrients

high pressure

low temperatures

explanation: 1. few nutrients:   open-ocean zone is located way far from the land, which is the main source of the essential nutrients.2. high pressure: pressure increases by 1 atmosphere for every 10 meters increase in depth.3. ample sunlight: a large fraction of the sunlight is reflected back to the atmosphere from the sea surface. 4. varying salinity: below the thermocline, the water is isolated from the atmosphere so the salinity remains stable over the year.5. low temperatures:   the temperature of open-ocean zone ranges from a low of -2°c to an average of 17°c

c. is the correct answer