Question bank

Pick an answer to see if you're right — with an explanation.

All topics Python SQL / MySQL Data Science NumPy Pandas Matplotlib Machine Learning Deep Learning Artificial Intelligence Large Language Models Django APIs Git & GitHub Power BI Excel Statistics

Deep LearningEasy

What does `model.eval()` change?

aIt disables gradient computation entirely

bIt freezes all parameters so they cannot be trained

cIt moves the model to the CPU

dIt switches layers like dropout and batch norm to inference behaviour

DjangoEasy

Which default permission codename does Django create for editing a `Product` in app `shop`?

ashop.edit_product

bshop.change_product

cshop.update_product

dshop.modify_product

ExcelEasy

In Data Validation, which Allow option creates a dropdown list in a cell?

aDecimal

bCustom

cList

dText length

Git & GitHubEasy

Where do GitHub Actions workflow files live?

aIn the repo root as actions.yml

bIn GitHub account settings only

cIn a .git/hooks folder

dIn the .github/workflows/ directory

Large Language ModelsEasy

Which approach is best for answering questions about a price list that changes every week?

aFine-tuning every week

bA longer system prompt with old prices

cHigher temperature

dRAG over the current price list or a tool that queries it

Machine LearningEasy

Why must features usually be scaled before k-means?

aK-means only accepts values between 0 and 1

bScaling makes it run on GPUs

cScaling removes outliers

dIt uses distances, so large-unit features would dominate

MatplotlibEasy

Why should you avoid using only red vs green to separate profit and loss series?

aMatplotlib cannot draw red

bGreen lines are slower to render

cIt increases file size

dMany readers have red-green colour vision deficiency

NumPyEasy

What is the shape of `np.arange(12).reshape(3, -1)`?

a(3, 3)

b(12, 3)

c(3, 12)

d(3, 4)

PandasEasy

Which dtype is best for a column with only 5 distinct payment modes repeated across millions of rows?

aobject

bfloat64

cstring

dcategory

Power BIEasy

Which object is computed row by row and physically stored in the model at refresh time?

aA measure

bA slicer

cA report-level filter

dA calculated column

PythonEasy

With `from pathlib import Path`, what is `Path('data/sales.csv').stem`?

asales

bsales.csv

c.csv

ddata

SQL / MySQLEasy

In `EXPLAIN` output, what does `type = ALL` indicate?

aAll indexes were used

bA full table scan

cThe query returns all columns

dThe result is cached

StatisticsEasy

Which test checks whether two categorical variables, such as city and payment method, are related?

aOne-way ANOVA

bChi-square test of independence

cPearson correlation

dPaired t-test

PythonEasy

What is `3 // 2`?

a1.5

SQL / MySQLMedium

Which is best for storing money in MySQL?

aDECIMAL

bFLOAT

cDOUBLE

dVARCHAR