Linear Transformations and Matrices Practice Test

A poster is uniformly scaled by $k=0.5$ using $S=0.5\ 0;\ 0\ 0.5$. Based on the scenario, what changes occur to the dimensions?

A CAD tool rotates a model about the $z$-axis by $90^\circ$ using $R=0\ -1\ 0;\ 1\ 0\ 0;\ 0\ 0\ 1$. Based on the scenario, what is $R\langle 2,1,5\rangle$?