1
D465 - Data Applications EXAM
Questions and Answers (Verified
Answers) (Latest Update 2025) UPDATE!!
sR and Python similarities - (ANSWER)Both widely used in data science with
extensive libraries.
R unique challenges - (ANSWER)Steeper learning curve, limited web dev
capabilities.
Advantage of storing code in R - (ANSWER)Allows reproducibility and
collaboration among analysts.
Programming languages and use cases - (ANSWER)Python: web dev, data science,
ML, automation.
MIN function in spreadsheets - (ANSWER)Returns the smallest value in a cell
range.
COUNTIF function in spreadsheets - (ANSWER)Counts cells meeting a specified
condition.
Pivot table elements - (ANSWER)Rows, columns, values, filters for data
aggregation.
,2
SELECT command in SQL - (ANSWER)Retrieves data from one or more database
tables.
JOIN commands in SQL - (ANSWER)INNER, LEFT, RIGHT, FULL OUTER JOIN types.
Delimiter for code chunks - (ANSWER)Triple backticks or markup to define code
sections.
Output formats for documents - (ANSWER)HTML, PDF, Word (docx), Markdown.
Presentation formats - (ANSWER)Slides, Dashboards, Interactive web apps.
Knit button in R - (ANSWER)Compiles R Markdown into desired output formats.
Symbol for comments in R - (ANSWER)Pound sign (`#`) precedes comments in R.
Nested function usage - (ANSWER)Simplifies operations, improves code
readability.
Logical operators - (ANSWER)AND (&&), OR (||), NOT (!).
Advantage of tidyverse - (ANSWER)Cohesive data manipulation packages in R.
,3
Functions in ggplot2 - (ANSWER)ggplot(), geom_point(), geom_line(), aes().
Plus sign in ggplot2 - (ANSWER)Adds layers to ggplot objects for customization.
Common errors in ggplot2 - (ANSWER)Incorrect aesthetic mappings, syntax
misunderstanding.
Basic aesthetic attributes in ggplot2 - (ANSWER)x-axis, y-axis, color for plot
customization.
Smoothing line usage - (ANSWER)Visual representation of trends in data.
dplyr filter() function - (ANSWER)Subset rows based on specific conditions in R.
VLOOKUP function in spreadsheets - (ANSWER)Searches for values in a vertical
column.
Locking table array in VLOOKUP - (ANSWER)Prevents range changes for formula
accuracy.
Different JOIN functions in SQL - (ANSWER)INNER, LEFT, RIGHT, FULL OUTER JOIN
types.
, 4
COUNT vs. COUNT DISTINCT in SQL - (ANSWER)COUNT: total rows, COUNT
DISTINCT: unique values.
SELECT statement usage in SQL - (ANSWER)Retrieving data from one or more
tables.
FROM statement in SQL - (ANSWER)Specifies tables for data retrieval in SQL
queries.
Tibbles vs. data frames - (ANSWER)Modernized data frames with improved
features.
Main operators in R - (ANSWER)Arithmetic, relational, logical, assignment
operators.
sample() function for biased data - (ANSWER)Creates random unbiased data
samples.
Fill in the blank: The spreadsheet function _____ returns the number of cells
within a range that match a specified value.
COUNTIF
ARRAY
COUNT DISTINCT
D465 - Data Applications EXAM
Questions and Answers (Verified
Answers) (Latest Update 2025) UPDATE!!
sR and Python similarities - (ANSWER)Both widely used in data science with
extensive libraries.
R unique challenges - (ANSWER)Steeper learning curve, limited web dev
capabilities.
Advantage of storing code in R - (ANSWER)Allows reproducibility and
collaboration among analysts.
Programming languages and use cases - (ANSWER)Python: web dev, data science,
ML, automation.
MIN function in spreadsheets - (ANSWER)Returns the smallest value in a cell
range.
COUNTIF function in spreadsheets - (ANSWER)Counts cells meeting a specified
condition.
Pivot table elements - (ANSWER)Rows, columns, values, filters for data
aggregation.
,2
SELECT command in SQL - (ANSWER)Retrieves data from one or more database
tables.
JOIN commands in SQL - (ANSWER)INNER, LEFT, RIGHT, FULL OUTER JOIN types.
Delimiter for code chunks - (ANSWER)Triple backticks or markup to define code
sections.
Output formats for documents - (ANSWER)HTML, PDF, Word (docx), Markdown.
Presentation formats - (ANSWER)Slides, Dashboards, Interactive web apps.
Knit button in R - (ANSWER)Compiles R Markdown into desired output formats.
Symbol for comments in R - (ANSWER)Pound sign (`#`) precedes comments in R.
Nested function usage - (ANSWER)Simplifies operations, improves code
readability.
Logical operators - (ANSWER)AND (&&), OR (||), NOT (!).
Advantage of tidyverse - (ANSWER)Cohesive data manipulation packages in R.
,3
Functions in ggplot2 - (ANSWER)ggplot(), geom_point(), geom_line(), aes().
Plus sign in ggplot2 - (ANSWER)Adds layers to ggplot objects for customization.
Common errors in ggplot2 - (ANSWER)Incorrect aesthetic mappings, syntax
misunderstanding.
Basic aesthetic attributes in ggplot2 - (ANSWER)x-axis, y-axis, color for plot
customization.
Smoothing line usage - (ANSWER)Visual representation of trends in data.
dplyr filter() function - (ANSWER)Subset rows based on specific conditions in R.
VLOOKUP function in spreadsheets - (ANSWER)Searches for values in a vertical
column.
Locking table array in VLOOKUP - (ANSWER)Prevents range changes for formula
accuracy.
Different JOIN functions in SQL - (ANSWER)INNER, LEFT, RIGHT, FULL OUTER JOIN
types.
, 4
COUNT vs. COUNT DISTINCT in SQL - (ANSWER)COUNT: total rows, COUNT
DISTINCT: unique values.
SELECT statement usage in SQL - (ANSWER)Retrieving data from one or more
tables.
FROM statement in SQL - (ANSWER)Specifies tables for data retrieval in SQL
queries.
Tibbles vs. data frames - (ANSWER)Modernized data frames with improved
features.
Main operators in R - (ANSWER)Arithmetic, relational, logical, assignment
operators.
sample() function for biased data - (ANSWER)Creates random unbiased data
samples.
Fill in the blank: The spreadsheet function _____ returns the number of cells
within a range that match a specified value.
COUNTIF
ARRAY
COUNT DISTINCT