> **米追加関税第４弾 ３８０５品目対象、スマホも 措置発動は６月下旬以降か**

I understand this as, "The USA has added additional tarrif/tax on 3805
articles/products (according to bullet point 4), which includes smartphones.
To be put into practice from third half of June"

What role does か at the end play here? Wouldn't the headline be fine without
it or is it some kind of transformation か like コンピューターか (computerization) ?

Article for reference:
<https://www.sankei.com/world/news/190514/wor1905140011-n1.html>
CC BY-SA 4.0
2019-05-14T03:22:14.430
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2019-05-14T03:22:14.430
18021
question
grammar sentence-final-particles
What does か at the end of the headline signify?