Ten Numeric Recall Questions

A closing set of purely figure-based questions, drawn directly from the numeric quick-reference table above — useful for a final speed-drill immediately before an exam.

158. What is the Caspian Sea's approximate surface area? — Roughly 371,000 km².
159. What is Lake Baikal's approximate maximum depth, and what share of the world's unfrozen fresh surface water does it hold? — Roughly 1,642 m; roughly 20%.
160. What is Lake Superior's approximate surface area? — Roughly 82,100 km².
161. At roughly what elevation does Lake Titicaca sit? — Roughly 3,812 m above sea level.
162. What is the Dead Sea's approximate depth below sea level and approximate salinity? — Roughly 430 m below sea level; roughly 34% salinity.
163. What is Lake Tanganyika's approximate length and maximum depth? — Roughly 673 km long; over 1,400 m deep.
164. What is Wular Lake's seasonal area range? — Roughly 30 km² in the dry season to roughly 190 km² at maximum flood extent.
165. What is Vembanad Lake's approximate length, and what superlative does this figure support? — Roughly 96 km; it makes Vembanad India's longest lake.
166. What is Lonar Lake's approximate crater diameter, depth, and estimated age? — Roughly 1.8 km diameter, roughly 137 m deep, an impact estimated at roughly 35,000–50,000 years old.
167. At roughly what elevation does Pangong Tso sit, and what fraction of its length lies within India? — Roughly 4,225 m; only around a third of its roughly 134 km length.
168. Name the Senegalese lake that is permanently pink like Lake Hillier, and the livelihood that distinguishes it from Hillier's uninhabited setting. — Lake Retba (Lac Rose); a real artisanal salt-harvesting economy, since it sits close to Dakar.
169. Name four Indian lakes/reservoirs where regulated water-sports tourism (boating, kayaking, sailing) forms a deliberate part of the civic tourism identity. — Any four of: Bhopal's Upper Lake, Sukhna Lake (Chandigarh), Umiam Lake (Meghalaya), and Udaipur's lake cluster (Pichola/Fateh Sagar).
170. What prior clearance do trekkers to Roopkund typically need before undertaking the high-altitude trek, and why? — Prior permits from state forest/tourism authorities, given the sensitivity of the skeletal remains and the difficulty of the high-altitude terrain.
171. What two permit types govern travel to Gurudongmar Lake for Indian citizens and foreign nationals respectively, and why is such a permit regime required? — An Inner Line Permit for Indian citizens and a Protected Area Permit for foreign nationals; required because of the lake's proximity to the international border.
172. Name Loktak Lake's traditional community-managed ring-net fishing technique, and briefly describe how it works. — Athaphum fishing — a ring-shaped section of phumdi is cut and anchored as a floating fish-attracting enclosure, with fish periodically harvested from within it.
173. Where and when is Dal Lake's floating vegetable market held, and how do sellers reach it? — At dawn near the Gagribal area, with growers paddling small wooden shikara boats loaded with produce.
174. What formal conservation rule reinforces Khecheopalri Lake's religious sanctity? — A prohibition on motorised boating and fishing, with the surrounding forest protected as a dedicated conservation area.
175. Name the four combined functions Hirakud Reservoir was built to serve, and the year it was completed. — Irrigation, hydropower generation, flood moderation, and (more recently) industrial water supply; completed in 1957.
176. What specific construction-material superlative is the Nagarjuna Sagar Dam frequently cited for? — One of the world's largest masonry dams.
177. Name the four distinct dam/reservoir superlative categories covered in this book (height, length, historical significance, and construction material), with one Indian example of each. — Height — Tehri Dam; length — Hirakud Dam; historical significance — Bhakra Dam; construction material — Nagarjuna Sagar Dam (masonry).