According to the rules for significant figures, simple decimal subtraction is done. But since 15.54 is only accurate to the hundredths place, then the resulting difference should also be rounded off to the nearest hundredths. This is shown below:
508.9538 - 15.54 = 493.4138
Rounding off to the nearest hundredths:
= 493.41
A neutron is a particle that it doesn´t carries charge, a neutron is a neutral particle.
An electron is a particle that carries a negative charge, and a proton is a particle that carries a positive charge.
b.False.
Good luck.