A characteristic or quantity of interest that can take on ...

[armygirl]

A characteristic or quantity of interest that can take on different values is a(n)
 a. variable.
  b. observation.
  c. record.
  d. quality.

Question 2

Imputing values is valid only if the variable values are We may replace missing values with the variable's mode, mean, or median, but only if the variable values are
 a. not missing at random (MNAR).
  b. missing at random (MAR).
 
  c. missing completely at random (MCAR).
  d. Classification and Regression Trees (CART).

[jxjsniuniu]

Answer to Question 1

a
RATIONALE: A variable is a characteristic or quantity of interest that can take on different values.

Answer to Question 2

c
RATIONALE: Options for replacing the missing entries for a variable include replacing the missing value with the variable's mode, mean, or median. Imputing values in this manner is truly valid only if variable values are MCAR; otherwise, we may be introducing misleading information into the data.

[armygirl]

Gracias!

[alvinum]

Great answer, keep it coming