Please can you explain how to do the following:
a) a non-smoker with low blood pressure has a plasma chloesterol concentration of 5mmol per litre. Over a period of time this concentration increases to 8mmol per litre. By how many times has this risk of heart disease increased? Show your working.
b) Two non-smoking men with low blood pressure both have plasma chloesterol concentrations of 5mmol per litre. One of them starts to smoke and the plasma chloesterol concentration of the other increases to 7mmol per litre. Which man is now at the greater risk of heart disease? Explain your answer.
Many thanks