How to increase the width of a drop down field?

How can I increase the size of my first drop down menu so it fits the last selection completely?

You should be able to increase the size of the first drop down by injecting this CSS code: 

#input_7 {

    width : 298px !important;

    max-width : none;

}

The form currently has the property max-width with a value already set, so the field can not have more than the specified value, this is why I suggest to add a value of none to the max-width property, as shown in the above code. 

Also, if you want to apply this code to other drop downs in your form then you will need to get the ID of the field that you want to affect, the guide below will help you to get the ID  of the field: 

How-to-find-Field-IDs-Names

The guide below will help you to inject the code to your form: 

How-to-Inject-Custom-CSS-Codes

Hope this helps.