A set of observations on a variable measured at successive points ...

[bobbie]

A set of observations on a variable measured at successive points in time or over successive periods of time constitute a
 a. geometric series. b. time invariant set.
  c. time series. d. logarithmic series.

Question 2

Using multiple lines on a line chart or employing multiple charts is an alternative to a
 a. column chart. b. line chart.
  c. two-dimensional graph. d. three-dimensional chart.

[LegendaryAnswers]

Answer to Question 1

c
RATIONALE: A time series is a sequence of observations on a variable measured at successive points in time or over successive periods of time.

Answer to Question 2

d
RATIONALE: As an alternative for a three-dimensional (3-D) chart, we consider the use of multiple lines on a line chart or employing multiple charts.

[bobbie]

Wow, this really help

[xiazhe]

Great answer, keep it coming