The diagram represents an atom of an element key e = electron = 4
n = neutron = 5
p = proton = 4
Which symbol gives this information?

a gas, having a molecular weight of 13 kg/kmol and a kinematic viscosity of 0.25 cm2/s, flows through a pipe 0.25 m internal diameter and 5 km long at the rate of 0.4 m3/s and is delivered at atmospheric pressure.

i think that the answer is c

b) nuclear ive learned that in a pedtrodic table