Is this a function?
{(2, 9),(5, 8),(19, 9)}

Yes

Step-by-step explanation:

As long as no x values repeat it is considered a function

In the given set no x values repeat therefore it is a function

Yes.

Step-by-step explanation:

Each input has exactly one output. Therefore, this is indeed a function.

step-by-step explanation:

two pairs of adjacent sides are of equal length. this implies that one diagonal divides the kite into congruent triangles, and so the angles between the two pairs of equal sides are equal in measure. it also implies that the diagonals are perpendicular.

answer: the sun

explanation:

water cycle describes the evaporation of water from earth's surface, formation of clouds and precipitation water back onto the surface of earth. seventy percent of the earth is covered with water in the form of seas and oceans. the heat of the sun causes the evaporation of water from the surface of the ocean. the water vapors rise and condense to form water droplets. the collection of these water droplets form clouds which rain down again.

the evaporation of the oceans surface water as part of the water cycle is caused by the sun