Answer:
An atom is the smallest particle in a chemical element that holds its chemical properties. Although in the past it was thought impossible to break an atom, within modern chemistry we know that an atom is composed of subatomic particles, which compose the atomic model:
1) electrons, which have a negative charge, such a small size that it is immeasurable, and a mass much smaller than the other two subatomic particles; 2) protons, which have a positive charge; and 3) neutrons, which have no charge.
The protons and neutrons form a dense and massive atomic nucleus, which is called multipons nuclei. The electrons form a cloud of electrons that surround the nucleus.
The theory of tectonic plates explains that large convectional currents occuring in the mantle(as a result of magma) are the reasons plates,and so continents,are moved. Note movement occurs in the boundary in between the plates.
"A. labelling food supplies" and "B. monitoring water supplies" are both public health measures that have helped fight disease. Vaccinations are essential to public health.
The correct answer is - B. Beak size determines what the bird can eat.
The beak of a bird can come in many different shapes and sizes. It can be pointy, long, short, rounded, scythe-like, thin, thick... All of those shapes and sizes have a specific role, and that role is to enable the bird to feed itself with certain type of food source. Every food source requires certain type of beak in order for the bird to be efficient in getting its nutrition, so depending on hat the bird eats, we can easily see a pattern in the beaks, where birds that eat nuts have one strong and shorter beak, the ones that eat warms and insects have thin, pointy one, the predator birds have claw like, sharp beak...
