A famous study examined the smoking habits of British doctors and whether or not the doctors developed various types of cancers. Participants responded to questionnaires about their smoking habits and health in 1951, 1957, 1966, and many more times all the way up to 2001. What type of observational study is this

How many lines can be drawn through points j and k? 0 1 2 3

The figures below are made out of circles, semicircles, quarter circles, and a square. find the area and the perimeter of each figure and give your answers as a completely simplified exact value in terms of π (no approximations).

Needmax recorded the heights of 500 male humans. he found that the heights were normally distributed around a mean of 177 centimeters. which statements about max’s data must be true? a) the median of max’s data is 250 b) more than half of the data points max recorded were 177 centimeters. c) a data point chosen at random is as likely to be above the mean as it is to be below the mean. d) every height within three standard deviations of the mean is equally likely to be chosen if a data point is selected at random.