Which description includes a vector quantity?
a the car is moving at 70 miles/hr.
b the car's velocity changes at 9.8 m/s2.
c the plane is flying at 850 miles/hr.
d the box moved left 20 meters.

D The box moved left 20 meters.

Explanation:

Let's start by explaining that a vector is one that has a numerical value along with its units (called a module) and a direction, while a scalar is only determined with a number and its corresponding units, without direction.  

Then, if we are given a quantity with only a numerical value along with its units we will have a scalar, and when we have a quantity with its numerical value along with its units and also the direction is given, we will have a vector.

So, according to this explanation, the only option that fullfils the conditions of a vector is D:

The box moved left 20 meters.

Because we have a numerical value (20) with ist units (meters) and its direction (to the left).

correct it is c.) b b

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