Ineed to write down like meanings in those words.

Bilateral: When something is bilateral it has two sides or it affects both sides of something. Discussions between two political parties are called bilateral because both sides get to share their views. Bilateral comes from Latin: bi means "two" and lateralis means "belonging to the side."

Endotherm: is an organism that maintains its body at a metabolically favorable temperature, largely by the use of heat set free by its internal bodily functions instead of relying almost purely on ambient heat

Subspecies: In biological classification, the term subspecies refers to one of two or more populations of a species living in different subdivisions of the species' range and varying from one another by morphological characteristics. ... In the wild, subspecies do not interbreed due to geographic isolation or sexual selection

Arthropod: Arthropoda, such as an insect, spider, or crustacean.

Micrometer: an instrument used with a telescope or microscope for measuring very small distances. 2 : an instrument having a rod moved by fine screw threads and used for making exact measurements. micrometer.

Hypothermia: Hypothermia is a potentially dangerous drop in body temperature, usually caused by prolonged exposure to cold temperatures. The risk of cold exposure increases as the winter months arrive. But if you're exposed to cold temperatures on a spring hike or capsized on a summer sail, you can also be at risk of hypothermia.

Polymorph: Polymorphism is the ability of a substance to crystallize into different crystalline forms. These crystalline forms are called polymorphs or crystalline modifications. Polymorphs have the same liquid or gaseous state but they behave differently in the solid state.

Hope this helped!!!

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.