2. A steel ball of mass 140 g rolls down a frictionless plane, inclined at 30° to the horizontal, with a uniform acceleration equal to
A. 20.0 ms-2
B. 10.0 ms-2
C. 8.7 ms-2
D. 5.0 ms-2​

Your answer is 120miles 

In atoms, the electron carries a negative elementary or unit charge; the proton carries a positive charge. the two types of charge are equal and opposite. in an atom of matter, an electrical charge occurs whenever the number of protons in the nucleus differs from the number of electrons surrounding that nucleus.