Emergency room health care tends to have a demand curve that is very steeply sloped, while elective surgery does not. why? also, health care insurance and vacation spending tend to have a negative cross price elasticity of demand for many people. why?

Hey there!

For your first question, consider the difference between emergency care and elective surgery. Elective surgery is planned out in advance and is considered a luxury to those who can pay for it only. In some situations, people can opt out of treating something with surgery, especially if it's expensive, and may try other methods of treating what they have if other options exist. Also, as the price of a surgery procedure gets higher, less people will be able to pay for it, decreasing the demand. On the contrary, when it's an emergency, people will often value the life of the urgent patient above all else, including money. Therefore, it can be assumed that urgent care will always be demanded regardless of its price fluctuation. 

For your second question, consider the general consensus of people who purchase health care (in general). These people likely think about the possibility of falling ill and needing the health care in the first place. These people also likely think of all that could happen on vacation, especially to foreign countries where immunities and illnesses could be very different, and would like to minimize the possibility of getting ill as much as possible. So, it would make sense that someone who buys more health care would spend less on vacationing and vice versa. 

Hope this helped you out! :-)