This week on Artwaves: Stock Schlueter, Elaine Benjamin and Michelle Murphy-Ferguson. All three are North Coast Open Studios charter artists. They discuss their current work, influences and the importance of Open Studios to them individually and to the Humboldt County community as a whole. The 20th annual North Coast Open Studios continues this Saturday and Sunday, June 9 and 10, from 10 a.m. to 5 p.m. Visit northcoastopenstudios.com for maps to studios. You can listen to the program in the