For each pair of physics quantities, type in 'i' if the pair are inversely proportional to one another or 'd' if their relationship is one of direct proportionality
Inversely proportional - as one quantity decreases in magnitude, it forces the other to increase in magnitude
Directly proportional - as one quantity increases in magnitude, it forces the other to increase in magnitude too
If the second quantity is squared, then type in the letter 'i' or 'd' twice (e.g. if 'x' is inversely proportional to 'y-squared', type 'ii')