gadolinium oxide, a colorless powder which absorbs carbon dioxide from the air, contains 86.76% gd (atomic number 64) by mass. what is the percent by mass of oxygen in this compound?

answer: the mildest forms of push polling are designed merely to remind voters of a particular issue. for instance, a push poll might ask respondents to rank candidates based on their support of an issue in order to get voters thinking about that issue. many push polls are negative attacks on other candidates.

what are the options and what is the paragraph?