We know that 3.3 light years (ly) = 1.0 pc. Calculate the distance to the star Alpha Centauri in light years. Express your result with the appropriate number of significant figures.

You can simply multiply these numbers together since it's just a scaling factor:

Distance = 1.3 x 3.3 ly = 4.39ly.

An "appropriate" number of significant figures would be 2, since you have 2sf in your original data. So the answer should be 4.3ly (to 2 significant figures).