DA Data Analysis Tools and Programming 3

Question 1

What does the pandas .fillna() method do?

Accepted Answer

Fills missing NaN values with a specified value or method

Answer

Drops rows with NaN values

Answer

Fills all cells with zeros

Answer

Fills empty string columns with NaN

Question 2

What is the purpose of Excel's IF function?

Accepted Answer

Returns one value if a condition is true and another if it is false

Answer

Looks up a value in a range

Answer

Counts cells matching a condition

Answer

Calculates compound interest

Question 3

Which Python library is most commonly used for data visualization?

Accepted Answer

Matplotlib

Answer

Pandas

Answer

NumPy

Answer

Scikit-learn

Question 4

What does 'vectorization' mean in the context of pandas or NumPy?

Accepted Answer

Applying operations to entire arrays without explicit Python loops

Answer

Converting data to vector image format

Answer

Encoding text as numeric vectors

Answer

Compressing large DataFrames

Question 5

What is the purpose of Excel's SUMIF function?

Accepted Answer

Sums cells in a range that meet a specified condition

Answer

Counts cells meeting a condition

Answer

Returns the largest conditional value

Answer

Averages values meeting two conditions

Question 6

What does the pandas .drop_duplicates() method do?

Accepted Answer

Removes rows that are exact duplicates of other rows

Answer

Drops columns with duplicate names

Answer

Drops columns with constant values

Answer

Removes rows with missing values