Mei Li:
The 21st century's second and last solar transit (across the Sun) of what planet happened in 2012??
Shuai Zheng:
venus
Mei Li:
Which metal has a low-grade version called spelter, often used for sculptural casting??
Shuai Zheng:
zinc
Mei Li:
"One of Canada's UNESCO World heritage sites is ""Head-Smashed-In Buffalo Jump"", which was used for 5,500 years by which indigenous people to kill buffalo, by driving them off the 10 metre high cliff?"?
Shuai Zheng:
blackfoot