The zero vector in R4 is a. [0,0] b. [0,0,0,0] c. [0,0,0] d. None of these If u=[5,2,3] and v=[6,−7,3], then 4u+5v is a. [11,−5,6] b. [50,−27,27] C. [50,−5,6] d. [20,8,12]