Sort the following cellular components to reflect the centrifugal force required to sediment them by preparative ultracentrifugation, from low to high force required. Your answer would be a four-letter string composed of letters R, M, L, and N, e.g. LRNM.
(L) Lysosomes
(M) Microsomes
(N) Nuclei
(R) Ribosomes (free cytosolic)