The error in the possessive construction is that, instead of passenger's, it should be "passengers'". The apostrophe should be after the letter "s" because the noun is in the plural form. The correct sentence would be "Passengers' concerns about cell phone use on planes are justified."
I will look into the day I will get to our place in about two weeks so that you could come over tomorrow to help us out with your work tomorrow morning
1, because it is supported throughout the whole paragraph.
