Below are pictures of ten galaxies, each followed by a text box. Using the text box, you will categorize each galaxy and explain why you chose the category. If you are uncertain about how to categorize a galaxy, explain why it was difficult to pick among the categories. In explaining your choices, you should refer to the descriptions of the galaxies above.

(a) assume the equation x = at^3 + bt describes the motion of a particular object, with x having the dimension of length and t having the dimension of time. determine the dimensions of the constants a and b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.) (b) determine the dimensions of the derivative dx/dt = 3at^2 + b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.)