Let a=⎡⎣⎢−6396−21⎤⎦⎥. we want to determine if the system ax=b has a solution for every b∈r3. select the best answer. a. there is a solution for every b∈r3 but we need to row reduce a to show this. b. there is a solution for every b∈r3 since 2< 3 c. there is not a solution for every b∈r3 since 2< 3. d. there is a not solution for every b∈r3 but we need to row reduce a to show this. e. we cannot tell if there is a solution for every b∈r3. solution: