WGU D465 Data Applications Pre Assessment | Questions and Answers | 2026 Update | 100% Correct

WGU D465 Data Applications Pre-
Assessment | Questions and Answers |
2026 Update | 100% Correct


R and Python similarities -CORRECTANSWER Both widely used in data science with
extensive libraries.

R unique challenges -CORRECTANSWER Steeper learning curve, limited web dev
capabilities.

Advantage of storing code in R -CORRECTANSWER Allows reproducibility and
collaboration among analysts.

Programming languages and use cases -CORRECTANSWER Python: web dev, data
science, ML, automation.

MIN function in spreadsheets -CORRECTANSWER Returns the smallest value in a cell
range.

COUNTIF function in spreadsheets -CORRECTANSWER Counts cells meeting a
specified condition.

Pivot table elements -CORRECTANSWER Rows, columns, values, filters for data
aggregation.

SELECT command in SQL -CORRECTANSWER Retrieves data from one or more
database tables.

JOIN commands in SQL -CORRECTANSWER INNER, LEFT, RIGHT, FULL OUTER
JOIN types.

Delimiter for code chunks -CORRECTANSWER Triple backticks or markup to define
code sections.

Output formats for documents -CORRECTANSWER HTML, PDF, Word (docx),
Markdown.

Presentation formats -CORRECTANSWER Slides, Dashboards, Interactive web apps.

,Knit button in R -CORRECTANSWER Compiles R Markdown into desired output
formats.

Symbol for comments in R -CORRECTANSWER Pound sign (`#`) precedes comments
in R.

Nested function usage -CORRECTANSWER Simplifies operations, improves code
readability.

Logical operators -CORRECTANSWER AND (&&), OR (||), NOT (!).

Advantage of tidyverse -CORRECTANSWER Cohesive data manipulation packages in
R.

Functions in ggplot2 -CORRECTANSWER ggplot(), geom_point(), geom_line(), aes().

Plus sign in ggplot2 -CORRECTANSWER Adds layers to ggplot objects for
customization.

Common errors in ggplot2 -CORRECTANSWER Incorrect aesthetic mappings, syntax
misunderstanding.

Basic aesthetic attributes in ggplot2 -CORRECTANSWER x-axis, y-axis, color for plot
customization.

Smoothing line usage -CORRECTANSWER Visual representation of trends in data.

dplyr filter() function -CORRECTANSWER Subset rows based on specific conditions in
R.

VLOOKUP function in spreadsheets -CORRECTANSWER Searches for values in a
vertical column.

Locking table array in VLOOKUP -CORRECTANSWER Prevents range changes for
formula accuracy.

Different JOIN functions in SQL -CORRECTANSWER INNER, LEFT, RIGHT, FULL
OUTER JOIN types.

COUNT vs. COUNT DISTINCT in SQL -CORRECTANSWER COUNT: total rows,
COUNT DISTINCT: unique values.

SELECT statement usage in SQL -CORRECTANSWER Retrieving data from one or
more tables.

, FROM statement in SQL -CORRECTANSWER Specifies tables for data retrieval in
SQL queries.

Tibbles vs. data frames -CORRECTANSWER Modernized data frames with improved
features.

Main operators in R -CORRECTANSWER Arithmetic, relational, logical, assignment
operators.

sample() function for biased data -CORRECTANSWER 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
VALUE -CORRECTANSWER COUNTIF

What is an example of an array in a spreadsheet?

All cells with number values
Cells D7, E14, and F20
The values in cells B2 through B31
All cells with values greater than 100 -CORRECTANSWER The values in cells B2
through B31

Which function will calculate the sum of the products of the corresponding items in the
arrays M1:M4 and P1:P4?

=SUMPRODUCT(M1:M4, P1:P4)
=MULTIPLY(M1:M4, P1:P4)
=PRODUCT(M1:M4, P1:P4)
=ARRAY(M1:M4, P1:P4) -CORRECTANSWER =SUMPRODUCT(M1:M4, P1:P4)

Fill in the blank: The _____ of a pivot table organize and group the selected data
horizontally.

columns
rows
filters
values -CORRECTANSWER rows

Which spreadsheet tool finds an average value using values generated within a pivot
table?