When talking about Acceleration ,what is significant about the about the sign(+ or -)?

Acceleration at its most basic is the act of increasing your running speed. From a standing start (or blocks), you explode into action. If you’re already running, you pick up the pace. Acceleration continues until you can no longer increase your speed, at which point you achieve maximum velocity (top-end speed). Acceleration seems simple enough. The plus means your increasing speed, the k=minus means your decreasing in speed.

Explanation:

whichever one it is, it's definitely not one that you included on the list you provided.

i believe it is b. what was the cause of the big bang

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