Atrue statement about mass is that:
(a.) mass is often measured with a spring scale
(b.) mass is expressed in pounds
(c.) as the force of earth's gravity on an object increases, the object's mass increases
(d.) mass is determined by comparing the mass of an object with a set of standard masses that are part of a balance

(c.) as the force of Earth's gravity on an object increases, the object's mass increases

Explanation:

Based on newton's law of gravitation "every particle of matter in the universe attracts every other particle with a force that is directly proportional to the product of the masses of the particles and inversely proportional to the square of the distance between them".

It is mathematically expressed as:

    F =

F is the gravitational force on either particle

m₁ and m₂ are the masses

r is the distance between particles

G is the universal gravitation constant.

From this expression, we see that the force of earth's gravity is directly proportional to mass.

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.

a boiling water reactor does not boil the water. a pressurized water reactor boils the water faster. a pressurized water reactor is heated directly by the core. a pressurized water reactor does not use fission.