How to save dropdown/checkbox menu choice AND placeholder value by clicking a unique button?

I'm very newbie on Jquery, here's my problems.

1) I have a dropdown menu and a placeholder to set, by clicking on a button I'd like to save both values. This is what I wrote to save the placeholder input value, how to save and use the dropdown menu value at the same time?

<select name="comparison" id="comparison" size="1">
    <option value=" " selected="selected"> -- </option> 
    <option value="minor"> < </option>
    <option value="equal"> = </option>
</select>
<input id="search-price" type="text" placeholder=" insert price..."/>
<button id="run-search-price">Search</button>
[....]
var runSearch = function () {
    var searchText = $('#search-price').val();        
    var queryPrice = {....}
    [...]
};    
$('#run-search-price').click(runSearch);

2) similar problem, I have a checkbox menu and a dropdown menu, I wanna save the values to use them for my queries, how to do that?

Hope this is clear, thank you in advance and sorry for possible mistakes.