Es un 1 punto
¿Cuál de los siguientes
material conductor de
electricidad? *
O Árbol
O Llave
O Hoja​

llave

Explanation:

it is a key, metal conducts electricity: una llave hecha de metal lleva a cabo la electricidad

in cartography, a contour line (often just called a "contour") joins points of equal elevation (height) above a given level, such as mean sea level. a contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness or gentleness of slopes.

explanation:

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.