An Apex trigger creates an Order__c record every time an Opportunity is won by a Sales Rep. Recently the trigger is creating two orders. What is the optimal method for a developer to troubleshoot this?

A developer is using a third-party JavaScript library to create a custom user interface in Visualforce. The developer needs to use JavaScript to get data from a controller method in response to a user action.
How can the developer accomplish this?

Refer to the code below:

When the code runs, it results In a System Limit Exception with the error message: Apex heap size too large.
What should be done to fix this error'

A company has a custom object, Sales Demo Request, that has a lookup to an Opportunity. It is required that a Sales Demo Request record be created when an Opportunity's Probability is greater than 50%. What is the optimal way to automate this?

How can Apex be used with Visual Workflow?