i think the answer is 3 4 5
I believe the answer is "Include ample fruits, vegetables, and fiber in the diet". The other answers had almost nothing to do with heart disease. Let me know if this helps any.
Independent variable in a investigation is the factor you control and change (e.g. in plant biology it could be light intensity, a concentration level of substances in added water or soil) that influence the dependent variable (in plant biology this would be the rate of photosynthesis).
There must be a number of groups to prove the influence of the independent variable on the dependent variable and trials to increase credibility of the results. Remember to include a control group where independent variable is not changed. (e.g. in measurement of light intensity on the rate of photosynthesis there must be a control where the light intensity is not manipulated to present the regular rate).
They involve the transfer of energy from the changes in state
