Strep throat: Classically strep throat does not cause a cough. It's possible you have/ had a viral upper respiratory infection. These usually resolve within 1- 2 weeks.
What are the Means and Extremes of Proportions? A proportion is just an equation where two ratios are equal, and each piece of the proportion has a special name.
Ok direct relationship or proportionality is a mathematical concept. This concept has been used to make the formulas of Laws of Motion but I don't think the other can be done. Since a mathematical relationship is an abstract concept and Laws of motion applies to bodies with mass.