Let B(t_2; t_1) be the price at time t_1 of a bond maturing at time t_2 with a unit face value. Prove that B(t_2;t_0) = B(t_2;t_1)B(t_1, t_0), using a no arbitrage argument. Assume continuous compounding and give the related relation for the corresponding returns r(t_2; t_0), r(t_2, t_1), r(t_1; t_0). Moreover, express the r's in term of B(t_2; t_0) and B(t_1; t_0)