
direct relationship
 as the x variable increases, the y variable also increases

inverse relationship
 as the x variable increases, the y variable decreases

cyclical relationship
 as the x variable increases, the y variable increases and decreases in a repeating pattern

static relationship
 as the x variable increases, the y variable remains the same

extrapolation
 when going beyond the data on a graph
 **although the inference may be on the graph, if it is not expressly stated on the graph, then it is extrapolation
 extrapolation is a form of inferencing

interpolation
staying within the given data on a graph

What is percentage error and how do you find it?
 difference between actual and measured x 100 =percentage error
 actual answer

What is classification and its benefits?
Classification is a system of organizing information, data, objects, or events in a meaningful way based on shared properties.
 Its benefits are:
 keeps us organized
 can find information or objects quickly
 increases efficiency
dichotomous key

What is density?
 The ratio between an object's mass to its volume.
  same material, same density, no matter the size

phrases to describe graphical relationships
 patterned
 nonlinear
 linear
 cyclic

What are the dependent and independent variables?
 Dependent  y
 Independent  x

What are the three ancient evidences of Earth's shape?
  top of ship is seen first when coming toward, top of ship is seen last when going away
  angle of polaris changes gradually and slowly
 ** polaris's altitude is always equal to one's latitude. polaris can only be seen in the northern hemisphere
  shadow of earth on moon during eclipse is always curved and indistinct
all prove that earth is spherical

What is earth's true shape?
Earth is an oblate spheroid, flat on poles, rounder at equator, due to centrifugal force. Therefore, gravity is greater at the poles and less at the equator.

What is the best modern evidence of Earth's shape?
Satellite photos from outer space.

What was Eratosthenes' method for determining circumference?
 proportion
 distance between two points = shadow angle
 circumference 360 degrees

What is earth's coordinate system based on?
(parallels) latitude and (meridians) longitude

Latitude
  run horizontally
  measure degrees north and south of the equator
  all parallel
  maximum value is 90
  never an equal distance apart because earth is an oblate spheroid

Longitude
  run vertically
  measure degrees east and west of the prime meridian, located at Greenwich, England
  meet at the poles
  at the equator they bulge

How large is each time zone?
15 degrees, because 15 degrees x 24 hours = 360 degrees, a full rotation
Some time zones aren't exactly 15 degrees due to cities.

How are points between latitude and longitude measured?
 ( ' ) = minutes
 ( " ) = seconds
60 minutes in a degree, 60 seconds in a minute

Why did the earth separate into layers?
Because when the earth was still forming, the molten parts separated due to density.

How is the atmosphere separated?
Based on temperature.

field
a region in which there is a measurable quantity of a given property at every point

vector field
any field described by both magnitude and direction
eg. gravity, magnetism, velocity

scalar field
only gives amount, size, or magnitude
eg. temperature, humidity, rainfall total, speed

isolines
lines on a map connecting points of equal value

Rules for isolines
  know the interval
  smooth curves
  no intersecting
  usually follow each other in patterns
  can end at the end of page
  individual isolines connect points of only one value

topographic map
a map on which structural features of a landscape are represented in 3d

How to determine slope on maps?
 closer lines = steeper slope
 far lines = low slope

determine direction of stream/river flow
  when contour lines cross a river, they point away from the direction the river is moving; they point upstream
  all streams lead to the ocean
  all streams flow from high to low elevation

hatcher marks
  indicate depressions
  same elevation as the lowest value of the adjacent lines

contour interval
difference in value between any two adjacent contour lines

