A
Before some of the greatest explorers in history were born, Vikings had already navigated (航海) their way around the world. But with no 1 (compass), satellites or radios, how did they manage 2 (map) the globe so impressively? The answer is 3 (simple) than you might expect - experience. Viking travelers studied the positions of the stars and the sun. Even the colour of the sea and movement of the waves would give them an 4 (indicate) of how close they were to land.
B
The Port of Shanghai has been the busiest in the world for 14 years running after 5 (overtake) the Port of Singapore in 2010. The seaport, situated at the mouth of the Yangtze river, 6 (grow) to cover an area of 1.5 square miles since it was opened in 1842. From here, 500 million tonnes of goods is handled in a year. There’s enough space at Shanghai to receive this huge shipment, most of 7 consists of coal, steel and machinery.
C
When a severe car crash occurs on a deserted road, the injured may not rely on nearby witnesses to call the emergency services. Now many modern smartphones 8 (equip) with crash-detection technology that uses data to determine when a car crash has occurred. An alarm 9 (play) by the smartphones will be sent to the services automatically. In an emergency situation the device detects 10 the crash takes place to share the location with first responders so that there’s a higher chance of survival for the crash victims.