Answer: [A]: "library card".
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Explanation: One would need a valid, government-issued photo ID card (i.e. that has not expires).
Although SOME library cards include one's picture, library cards do not constitute "valid ID's" because they are not "government-issued" and would, theoretically, be easy to be made fraudulently (e.g. not have security-issued seals and features).
Even "school ID's"; or "college ID cards"; even if "current" (e.g. currently enrolled" with a photo ID) would not be considered "official" and would only be considered "secondary ID".
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9 3/4 = 39/4 mi/m
68 1/4 = 273/4 min
39/4 mutiply by 273/4 = 10647 / 16 mi = 665.4 mi
"Formula of a circle" is too vague to be meaningful. Perhaps you meant, "Formula for the area of a circle in terms of its circumference."
The area of a circle in terms of its radius is A = πr^2. To put this formula to use, we have to know the radius of the circle. The circumference of a circle in terms of its radius is C = 2πr, so a formula for the radius is r = C / (2π).
Now let's find a formula for the area of a circle in terms of its circumference:
C C^2
A = πr^2 = π { ---------------- }^2 = ------------
2π 4π
or:
A = (C^2) / 4π
Because the equation is a positive number lower than the original