Answer:
2. have no negative particle
Explanation:
Helium atoms contains 2 neutrons and 2 protons (or 2 electrons). Thus, it has a mass number of 4 and atomic number of 2.
Alpha particles are heavy and positively charged, which make them to be deflected in a magnetic or electric charge. So, the helium atoms used as alpha particles for the gold foil experiment must have no negative particle.
Answer: D
Explanation:
Many unicellular organisms live in bodies of water and must move around to find food. Most often, they must obtain nutrients by eating other organisms. Plant-like protists, and some types of bacteria, can make their own food through photosynthesis.
Its common. In the last 10 million years, there have been 4 or 5 reversals per million years
I think it's the evaporation of water through the stomata :)