Can someone help me with these 2 questions?

The reaction NO (g) + Br2 (g) NOBr (g) is second-order in nitrogen oxide and first-order in bromine. The rate of the reaction is 1.6 x 10-8 mol/(L.min) when the nitrogen oxide concentration is 0.020 M and the bromine concentration is 0.030 M. (a) What is the value of k? (b) At what concentration of bromine is the rate 3.5 x 10-7 mol/(L.min) and [NO] = 0.043 M? (c) At what concentration of nitrogen oxide is the rate 2.0 x 10-6 mol/(L.min) and the bromine concentration one fourth of the nitrogen oxide concentration?

B. The decomposition of nitrosyl bromide is a second-order reaction: NOBr (g) NO (g) + Br2 (g) If the initial concentration of NOBr is 0.250 M, how much heat is evolved or absorbed per liter of solution in one minute? The rate constant is 0.80 L/(mol.s). The heats of formation are +82.2 kJ/mol for NOBr, +90.2 kJ/mol for NO, and +30.9 kJ/mol for Br2 as a gas