In Chile, the deepest earthquake occurred at 61.7 longitude at a depth of 540 km. If the rocks at the focus begin subducting 10 million years ago and are now 1000 km from the original position what is the average rate of subduction in Centimeters per year

Can you give me little more information

Humans have survived and thrived in mexico city by using technology to create greater access to land. when the spanish conquered the aztec capital, tenochtitlan, in the 16th century, they built mexico city by draining the lakes and filling in the lake water to create more arable land for agriculture. this technique of land reclamation has continued to be fundamental to human civilization in mexico city. 

As someone who have lived in northern moravia at industrial steel and coal city of ostrava, the closest point is b), but it is questionable. i am not sure how to compare efficiency of largest steel mill in czech republic in comparison to china which is the biggest exporter, but czech steel factories were modernized and run more efficient that 25-35 years ago, and been privatized and owned by mittal. the workforce had been shrinking, so not exactly sure what that c is pointing to (aging of workforce, size of it, or quality). northern moravia is a part of larger coal basin that extend to poland with large coal deposits. this was foundation for the steel industry in the 1800's together with large ore deposits that was mined in proximity of the beskidy mountains less than 25 miles from ostrava. the iron ore mines had been depleted for several decades, and since the late 70's when communists run the country, they were already importing soviet iron ore. coal mining within city of ostrava cased to exist in the 1990's due environmental issues, and also cost. the mines were getting deeper and more costly to operate and there is no more mining within ostrava. couple mines are still in operation in karvina county which is next to ostrava. currently the coal deposits south of the city were not opened due environmental issue which would mean destruction of third largest mountain range in the country. therefore, my conclusion is is b, as the ore and coal resources been shrinking. the biggest challenge not mentioned here is of course competition from russia, ukraine, and china, which can produce steel much cheaper.