Consider the following reaction: CH3Br(aq) + OH (aq) -- CH3OH(aq) + Br(aq) The rate law for this

Consider the following reaction:
CH3Br(aq) + OHˉ (aq) --→ CH3OH(aq) + Brˉ(aq)
The rate law for this reaction is first order in CH3Br and first order in OHˉ. When [CH3Br] is 5.0 × 10-3 M and [OHˉ] 0.050 M, the reaction rate at 298 K is 0.0432 M/s.
(a) What is the value of the rate constant?
(b) What are the units of the rate constant?
(c) What would happen to the rate if the concentration of OHˉ were tripled?
(d) What would happen to the rate if the concentration of both reactants were tripled?