Which of the following descriptions of a subatomic particle is incorrect?

a. A proton has a positive charge and a mass of approximately 1 amu.

b. An electron has a negative charge and a mass of approximately 0 amu.

c. A proton has a positive charge and is found in the nucleus.

d. A neutron has no charge and its mass is negligible.

e. A neutron has no charge and a mass of approximately 1 amu.