This depends.
First off, it would need to be an AT&T model, as Verizon models do not use a SIM card. Also, it depends on the UK carrier. Most would be compatible with AT&T's network, so yes, you should be able to use a US iPad 2 with a UK SIM. Although, take note that the iPad uses a microSIM, so the UK SIM card will have to be cut down to fit into the iPad.
yes
No, you can't you can run only US, UAE & Uk services on it.
US Cellular uses CDMA technology, not GSM, so, their phones do not use SIM cards.
No they use CDMA tec.
yes but you need to make sure the phone is unlocked so it will be able to work with any simcard
It depends, if you're with a certain network (carrier)like [uk] orange, three, vodafone [us]at&t, sprint etc, then no... unless its unlocked, or if you get it from t-mobile, then yes, you will be able to use a t-mobile sim card.
If the US mobile phone is in international roaming mode, you may be able to dial its normal US number. If the phone has swapped in a UK SIM card, you will need to dial the UK number.
No. Unless you have a UK to US power adaptor you can not use it.
yes you can, but you will have to use a UK proxy.
A new iPad will work with 4G LTE in the US. You will want to get a micro-SIM for a US-based data plan to keep the costs down.
NO. cellphone alone? YES . But with sim cards from USA? NO.
ofcourse they do