Data Science Mastery Quiz — Quiz

Framing questions, data collection, storytelling, projects and data privacy. · 10 questions

Question 1 of 10

What is the main difference between a metric and a KPI?

aA KPI is always a percentagebA KPI is a metric the business has agreed to steer bycMetrics come from SQL, KPIs from ExceldThere is no difference

Question 2 of 10

Which is a leading indicator for monthly revenue in an online store?

aLast quarter's profitbAnnual churn ratecAudited yearly turnoverdItems added to cart this week

Question 3 of 10

Under India's DPDP Act, 2023, the organisation that decides why and how personal data is processed is the…

aData FiduciarybData PrincipalcData ProcessordConsent Manager

Question 4 of 10

Which chart best shows how daily sales changed over six months?

aPie chartbScatter plotcLine chartdRadar chart

Question 5 of 10

Why should the API call below include `timeout=10`?

resp = requests.get(url, params={"page": 1}, timeout=10)
resp.raise_for_status()

aIt limits the response to 10 recordsbIt retries the request 10 timescIt caches the result for 10 secondsdIt stops the request waiting forever on an unresponsive server

Question 6 of 10

Why use a bound parameter like `:start` in `pd.read_sql(text(query), engine, params={...})` instead of an f-string?

aIt prevents SQL injection and handles quoting safelybIt makes the query run on the GPUcIt is required for SELECT statementsdIt automatically adds an index

Question 7 of 10

A chart titled "Sales by month" would be better titled…

a"Figure 1"b"Monthly sales data (₹)"c"Sales fell 18% after March in Lucknow"d"Chart of sales"

Question 8 of 10

What does this feature-engineering step create?

sales = sales.assign(
    festive=lambda d: d["date"].between("2025-10-01", "2025-11-30")
)

aA string column with the festival namebA boolean flag marking rows dated in Oct–Nov 2025cA new DataFrame with only festive rowsdAn error, because assign cannot take lambdas

Question 9 of 10

You SHA-256 hash customer mobile numbers without a salt and share the hashes. Why is this weak protection?

aSHA-256 output is reversible with a decryption keybHashes are longer than the original numberscHashing changes the data type to floatdThe space of 10-digit mobile numbers is small enough to hash every possibility and match

Question 10 of 10

Revenue fell 10% while order count stayed flat. Using a KPI tree (revenue = orders x AOV), where should you investigate first?

aFootfall and app sessionsbConversion ratecAverage order value: items per order and selling price after discountsdNumber of stores opened