Q1. List the ways to execute.

Here are the ways to execute:

Lethal Injection, Electrocution, Lethal Gas, Firing Squad, and Hanging are the popular ones now and also, scaphism, guillotine, republican marriage, cement shoes, elephant, walking the plank, bestiarii, mazzatello, upright jerker, sawing, flaying, blood eagle, gridiron, crushing, breaking wheel, the Spanish tickler, burning at the stake, bamboo, premature burial, ling chi, seppuku, brazen bull, Colombian necktie, crucifixion, hanged, drawn and quartered were the ways to execute. 

I heard that the hanging is used to execute in Japan but the government doesn't show further information. On the other hand, the U.S. shows how each state executes in the cite I found. There ware some that I was very surprised and seems really cruel... I trust these two pages I found because it gives us information in detail. 

Methods of Execution. http://www.clarkprosecutor.org/html/death/methods.htm25 of Humanity's Most Brutal Methods of Execution. List25. http://list25.com/25-of-humanitys-most-brutal-methods-of-execution/5/