On sunday evening kathy sent $x$ text message each hour for 3 hours and Arnold sent $y$ text message each hour for 5 hours . Which of the following represent the total number of message sent by kathy and Arnold on sunday evening ?

Question

$\begin{array}{1 1} (a)\;3x+5y \\ (b)\;5x+3y \\ (c)\;3xy \\(d)\;5xy \end{array}$