Q: Answer this question:

when a radioactive atom emits an alpha particle the original atom's mass number decreases by??

A: four

Q: Answer this question:

how many episodes in lie to me season 3??

A: 13

Q: Answer this question:

when did we get the world wide web??

A: In the 1980s

Q: Answer this question:

what grade is trevor in pay it forward??

A:
7th grade