Physics for the 21st Century This course covers a broad scale, from sub-atomic particle physics, through atomic and molecular physics, to cosmology. The video programs feature 22 case studies of researchers from leading research labs and universities who are breaking new ground in their fields.
How many people
should you survey for accurate polling results?
You have switched political camps once again and
are back working as a pollster for Stephanie Higgins.
It's the end of the campaign and Higgins knows that
what she says and does will make or break her. It's
your job to stay on top of what the voters are thinking
about each of the candidates.
It would be great if you could poll all of the
voters in the city, but there is no time for that.
Instead, you have to decide how many voters to poll
in order to get a result that you can be confident
about. You will ask them this question: