useless trivia: What Word Means: A First Name - A Chewy Candy - A Native Of Wales?

Questions

What group of superheroes display the number 4 on their chests?

What gun cannot be silenced, due to all the noisy gasses which escape the cylinder gap at the rear of the barrel?

What habit forming plant did Columbus find on his first new world trip?

What hair color of people do mosquitoes seem to be the most attracted to?

What hall of fame was opened in 1990 in Canastota, New York?