A nurse meаsured the blооd pressure оf eаch person who visited her clinic. Following is а relative-frequency histogram for the systolic blood pressure readings for those people aged between 25 and 40. Use the histogram to answer the question. The blood pressure readings were given to the nearest whole number. (a) Approximately what percentage of the people aged 25-40 had a systolic blood pressure reading between 130 and 139 inclusive? [x] (b) Given that 200 people were aged between 25 and 40, approximately how many had a systolic blood pressure reading under 120? [y]