Care este problema? Btw why are you speaking Romanian
Because the nucleus is made up of positively charged protons and neutrally charged neutrons, and no negatively charged particles, the charge of the nucleus will always be equal to the sum of the charges of its protons. A simpler way to say it is because each proton has a +1 charge, the charge of the nucleus will be the same as the number of protons in it.
The answer is B 1,500 meters since 1 kilometer to meters is 1,000 and u add the 500
Reflection: you look in the mirror.
Refraction: You put a straw in a glass of water, and it looks like it broke.
Absorption: If you have a black sweater and you wear it out in the cold, the black sweater is going to hold in heat better than a lighter sweater because the black sweater absorbs light .
I think the correct answer from the choices listed above is the second option. For endothermic reactions, the reactants have less energy than the products. Which would mean that energy should be added to the reaction for it to proceed. Hope this answers the question.