The nucleus of an atom is composed of 4 protons and 5 neutrons. How many electrons surrounded the nucleus of this atom? 1
4
5
9

In an atom the no. of proton is equal to the no. of electron

= 4 electron

More to know - Atom is made up of Proton , neutron and electron Proton is positively charged particle , electron is negatively charged particle and neutron is neutral in charge Proton and neutron together make up nucleus and located at the centre of atom Electron revolves around nucleus No. of electron/ proton = Atomic number No. of proton + neutron = Atomic mass

Julia would be observing a. static electricity was caused by her sweater rubbing against her shirt and transferring electrons. she didn't touch anything metal, so that would cancel out b.she most likely didn't rub her sweater against her hair either, so that cancels out c.she also didn't scoot across the carpet while trying to take her sweater off, that cancels out d.so that leaves a.a. is correct.