Evolution is:
a: fixed in one direction.
b: completely random.
c: neither entirely fixed nor entirely random

it cools slower in the earth meaning the crystals have more time to form than lava on the surface

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.

hi my name is ashlynn and im 15

these macromolecules could either be amino acids, proteins or nucleic acids. they are responsible for the chemical changes and reactions that affects largely the cell and its composition. take for instance the cytoplasm of the cell where these organelles are settled. these simple organelles are composed of macromolecules which ignites and catalyses different functions that enables cells, in macro-perspective in motion and metabolism. in intestines for example, metabolism happens and breaking down parts of a food to simpler compounds that are used and these nutrients delivered throughout the body and again broken down by into smaller components.

the correct answer is anaphylaxis.

anaphylaxis is a condition caused by insect bites, foods, medications, manifested by tongue swelling, shortness of breath, vomiting, low blood pressure. it sometimes may occur without an obvious reason. it is treated with epinephrine injection.other tretments include antihistamines and steroids,