does anyone know this !? it's a test

What is the best way to answer questions with a x expression in the question. for example 3x + 10x=?

Graph the line that represents a proportional relationship between d and t with the property that an increase of 33 units in t corresponds to an increase of 44 units in d. what is the unit rate of change of dd with respect to t? (that is, a change of 11 unit in t will correspond to a change of how many units in d? )

1yd 1 ft = 1 1/12 1 1/3 1 1/2 1 1/6