Why are light hydrocarbons stored under pressure?

The password for your online exam is: icecreamThe link for the online exam is in the Step 1 folder; you should have opened it in a new tab before you begin this test.Instructions:Before you begin your exam, hold up all sheets of paper you will be using to the camera to show that there is nothing written on them. If your instructor allows the use of formula sheets or a handheld calculator, please hold these up to the camera as well.Enter the password found above into the online exam tab open in Step 1 and complete the exam. Once completed, hold up each completed sheet of paper to the camera.Answer the Yes/No question below and proceed to the next question.DO NOT SUBMIT OR CLOSE YOUR TEST before answering all the questions.Question:I have completed and submitted my online exam, and I have held up all my sheets of paper (front and back) to record an image of them with the camera.

Why is a release of gas so dangerous?

If you increase pressure on a gas in a sphere, what will happen to the density of the gas?

If atmospheric pressure drops (a vacuum forms), what happens to boiling point?

Why is a relief valve required on any heated, closed vessel?

A tank is filled with hot crude oil and later cools. What outcome should be expected?

You notice that your pump is cavitating. What is the most likely cause?

A liquid hydrocarbon is heated before pumping. What will this do?  

What happens to the density of a gas when it is compressed?