Given a travel related situation, and given a specific question about the situation, summarize the question into a title

Input: Consider Input: So, I'm a high school student (international) trying to apply for a summer school in the United States. During the application process, there's a prompt that asks for my citizenship status, and one option is "Not a US citizen or permanent resident", while another one is "Not a US citizen or permanent resident but dependent of a visa holder". I'm not sure what does that mean. Hope somebody can explain it to me. Thanks!

Update: I asked them and they said they have useable B1 visas, so they should be visa holders I suppose? I don't understand why "dependent of a visa holder" is equivalent to "us citizen or permanent resident" as the answer below suggests (if we just take the words literally!)

Output: What does it mean to be "dependent of a visa holder"?

Input: Consider Input: Many credit cards offer free travel insurance when you purchase tickets using your credit card, and this will last for 40 days starting from the commencement of your trip.

But what if I purchase further flights and extend my holiday? e.g. I purchase a flight on the 39th day. Does this extend my travel insurance coverage or start a new insurance policy?

What if I purchase flights on day 41? Does this start a new Insurance policy as if it were a new trip?

Output: Credit Card travel insurance length

Input: Consider Input: I have an HTC A9s. I could not find it on the US page of the manufacturer so I went to the UK page.

According to the specs, it does have the US frequencies:

Network4

2G/2.5G - GSM/GPRS/EDGE:
850/900/1800/1900 MHz
3G UMTS (#UL):
850/900/1900/2100 MHz
4G LTE (#UHL):
FDD: Bands 1, 2, 3, 4, 5, 7, 8,12, 17, 28
TDD: Bands 38, 40
4G LTE (#UL):
FDD: Bands 1, 3, 7, 8, 20

Will I be able to use it in the US for calls and Internet?
Output: Using a European (GSM) cell phone in the US