Free DA0-001 Practice Test Questions 2026

Given the following data sample:

Which of the following best describes the data quality issue?

A. Data outlier

B. Consistent data

C. Duplicate data

D. Invalid data

A data analyst needs to calculate the mean for Q1 sales using the data set below:

Which of the following is the mean?

A. $2,466.18

B. $2,667.60

C. $3,082.72

D. $12,330.88

A county in Illinois is conducting a survey to determine the mean annual income per household. The county is 427sq mi (2.65q km). Which of the following sampling methods would MOST likely result in a representative sample?

A. A stratified phone survey of 100 people that is conducted between 2:00 p.m. and 3:00 p.m.

B. A systematic survey that is sent to 100 single-family homes in the county

C. Surveys sent to ten randomly selected homes within 5mi (8km) of the county’s office

D. Surveys sent to 100 randomly selected homes that are reflective of the population

A junior web developer is developing a new application where users can upload short videos. The first task is to create a homepage that shows the headline "Upload Your Short Videos" and a clickable button that says "upload now".

Which of the following HTML commands would help the developer to complete the task successfully?

A. < span >Upload Your Short Videos< /span >< button >upload now< /button >

B. < p >Upload Your Short Videos< /p >< p >upload now< /p >

C. < hl >Upload Your Short Videos< /h1 >< button >upload now< /button >

D. < hl >Upload Your Short Videos< /h1 >< hl >upload now< /h1 >

Which of the following statements would be used to append two tables that have the same number of columns?

A. UNION ALL

B. MERGE

C. GROUP BY

D. JOIN

An e-commerce company recently tested a new website layout. The website was tested by a test group of customers, and an old website was presented to a control group. The table below shows the percentage of users in each group who made purchases on the websites:

Which of the following conclusions is accurate at a 95% confidence interval?

A. In Germany, the increase in conversion from the new layout was not significant.

B. In France, the increase in conversion from the new layout was not significant.

C. In general, users who visit the new website are more likely to make a purchase.

D. The new layout has the lowest conversion rates in the United Kingdom.

A database consists of one fact table that is composed of multiple dimensions. Depending on the dimension, each one can be represented by a denormalized table or multiple normalized tables.

This structure is an example of a:

A. transactional schema.

B. star schema.

C. non-relational schema.

D. snowflake schema.

A data analyst who works for a government agency is required to obtain the average income of citizens. The list of citizens is given in the following table:

A value for one citizen's income is missing. Which of the following approaches should the data analyst take to solve this issue?

A. Replace the missing value with the average of the rest of the unemployed citizens.

B. Insert the value 0 into the field with the missing value.

C. Impute the mean of the other citizens' incomes into the field with the missing value.

D. Exclude employed citizens from the analysis.

An analyst wants to combine two data sets into a single spreadsheet. Column names from the first spreadsheet are listed in rows in the second spreadsheet. Which of the following is the first step the analyst should take to combine the data sets?

A. Blend

B. Merge

C. Concatenate

D. Transpose

A user imports a data file into the accounts payable system each day. On a regular basis. the field input is not what the system is expecting. so it results in an error for the row and a broken import process. To resolve the issue, the user opens the file, finds the error in the row, and manually corrects it before attempting the import again. The import sometimes breaks on subsequent attempts. though. Which of the following changes should be made to this process to reduce the number of errors?

A. Delete all incorrect inputs and upload the corrected file.

B. Have the user manually review the file for data completeness before loading it

C. Create a data field to data type validator to run the file through prior to import.

D. Spot-check the file prior to import to catch and correct field errors.

A publishing group has requested a dashboard to track submissions before publication. A key requirement is that all changes are tracked, as multiple users will be checking out documents and editing them before submissions are considered final. Which of the following is the BEST way to meet this stakeholder requirement?

A. Display the version number next to each submission on the dashboard.

B. Present a data refresh date at the top of the dashboard.

C. Confirm the dashboard is adhering to the corporate style guide.

D. Use permissions to ensure users only see certain versions of the submissions.

An analyst is building a new dashboard for a user. After an initial conversation with the user. the analyst created a mock-up of the dashboard. Which of the following best explains why the analyst created the mock-up?

A. To identify the dimensions and measures

B. To send to the client after deploying the dashboard to production

C. To confirm important details before dashboard development begins

D. To receive client approval for the final dashboard design