Question

When the reaction:

Answer 1

The last sentence is a little vague.
However, I will assume that by the last sentence you meant 
$Reaction~Rate=[CH_3Cl][H_2O]$
The reaction order respective to any substance is the value of the exponent on that substance in the Reaction Rate equation.
We see that the exponent on both the substance is 1 so the reaction order with respect to each substance is 1.