Sasha Urban editor“I was questioning what suffering was,” Amber Mark said to the crowd at the El Rey Theater in Los Angeles on Tuesday night. “What is life, what is the meaning of life — I could go on and on — but I need to be here for three more hours and smoke a lot of weed to get into it, and this is not a Ted Talk.”It was a heavy introduction for the smooth R&B of “What It Is,” a song from her recently released debut album, “Three Dimensions Deep,” but such is the multiplicity of Mark, whose live set found her exploring a melange of genres and vocal styles.Bathed in blood-red lighting and dancing so energetically that her mic pack came loose, Mark was in full form as she sang about “a feeling so strange / the way time never stays the same.” Her voice was in top gear, not once wavering as she climbed the scale from her signature raspy alto register to a softer, high-pitched falsetto.