please help with hw

(1) Dot Products Given the triangle ABC, A(2,1), B(4,1) and C(2,3): (la) Find the components of the vectors BA, BC and CA. (1b) Calculate a= | BC |, b= | CA | and c= | BAI. (1c) Use the Dot Product of BC and BA to find angle B. (1d) What is the area of AABC? atb+c (le) Let S = 2 , does Vs(s - a)(s - b)(s - c) equal the triangle area