Read the following email message. Complete the email by filling in the blanks. Select the best choice for each blank.

Hi Alex, I'm excited about our upcoming cave diving trip next month! I've been reviewing the safety protocols and equipment requirements. Since this will be your first cave dive, I wanted to make sure you're prepared. First, remember that 1 ..... This is the most important safety rule. Also, make sure you have the right certification level. Since you've completed your Advanced Open Water with about 30 logged dives, you qualify for the 2 .... certification, which will allow you to dive up to 60 meters from the surface as long as natural light is visible. For equipment, you'll need to invest in a good primary dive light. It's the most expensive piece of specialized gear at 3 ...., but absolutely essential. Don't forget to bring at least two backup lights with different battery types than your primary. I think the Blue Grotto System would be perfect for your first cave dive. It's rated as 4 .... difficulty with a maximum depth of 30 meters, well within our planned Nitrox gas limits. Speaking of gas, I recommend we use Nitrox for this dive since it offers 5 .... compared to regular air, though we'll need to stay above 34 meters. Let me know if you have any questions. I've already contacted Deep Blue Dive Shop about equipment rentals. Cheers, Jamie

Choose the best option.

Based on the email exchange, what can we determine about Jamie and Alex's relationship? 1 .... What is Jamie's main concern regarding the upcoming dive? 2 .... What would Alex need to do to qualify for a Full Cave Diver certification? 3 ....