This seems like an unreasonably high stoichiometry of Arp2/3 complexes per actin subunit; we now know that each Arp2/3 complex covers a few subunits, so there shouldn't be enough room on the filament to fit 1:1 Arp2/3 complex/actin

Microfilaments are also known as actin filaments; which, are protein filaments that are within the cytoplasm that form part of the cytoskeleton of an Eukaryotic Cell. They help in the process of cell movement via the actin working with another protein myosin that create muscle movements, cytoplasmic streaming, and cell division.