Write Sk 1.13+2 14+3•15+...+ Write SK+1- (Type your answer in factored form.) 1.13+2+14+3•15++= (Type your answer in factored form.) Simplify inside the parentheses on the right side. Do not multiply. Sk+1=(Type your answer in factored form.) What do we do with statements S, and Sk+1? OA. Use S, and S, to prove that Sk+1 is true. OB. Use SK and Sk+1 to prove that S, is true. OC. Use S to prove that Sk+1 is true. OD. Use Sk+1 to prove that S is true. To continue the proof by induction, begin with 1.13+2 14+3•15+...+k(k+ 12) = OA. n(n+12) OB. K(k+12) OC. k(k-12) OD. (k+ 1)(k+13) k(k+ 1)(2k +37) 6 which is assumed to be true, and add the k+ 1 term to both sides of the formula. What is this term?