They are looking for a circuit like this (a low pass filter).
https://upload.wikimedia.org/wikipedia/commons/e/e0/RC_Series_Filter_%28with_V%26I_Labels%29.svg
Read the Wikipedia article below and look at the "Gain and Phase" equations. Those will help you figure out the values for R and C. Start by picking a common value for C like 0.1uF and a low value for your gain like 0.001 (one thousand times smaller amplitude than your input), then solve for R. Also, ω is in radians per second (10k2pi in your case).
