Scientific ocean exploration began in the 19th century, using wooden sailing ships. At that time, explorers had none of the technological sophistication and tools available today. A comparison of modern-day exploration with the late 19-century journey of the HMS Challenger<span>illustrates the progress that science has made in ocean exploration.</span>
Answer:
A
Explanation:
All planets rotate about their axis, and revolve (orbit) around the sun.
I don't understand this question
Answer:
True
Explanation:
Given the available choices for answers... i'm going to guess.... True?
The trolleys have been reduced over the last decades, after their initial increase as a public transportation, when new and better ways were discovered/produced for transport, their decline has started.
The buses since their invention, had grown in number and became a very important part of every city's public transportation, and still are.
The rapid transit is the most recent one of the mentioned in here. It's popularity has grown, number increased, and is very practical because it is not causing traffic mess. It is very important transport asset nowadays and makes lives of millions of people much easier.
