Which of the following article titles indicates the probability of bias?
a. "study reveals rising rate of gun-related deaths for youth."
b. "expert says guns easier than ever to buy."
c. "gun casualties down in city."
d. "if we want to save our kids, we must control the sale of guns."

I find the last one to be biased: (even though i do agree with gun control...)

If We Want To Save Our Kids, We Must Control the Sale of Guns."

It suggests that the author argues that Guns threaten the children, which is an opinion, so it can come with a bias.

the remaining articles sound like an account of facts.

productive most commonly means: achieving or producing a significant amount or result.

explanation:

productive can also mean:

producing or giving rise torelating to or engaged in the production of goods, crops, or other commodities.

these depend on how the word productive is used. most likely productive will mean   achieving or producing a significant amount or result.