A patient complains of thirst, blurry vision, numb hands, and frequent urination. Which statement best explains why a doctor performed a blood glucose test on this patient? (A blood glucose test tests for levels of sugar in the blood.)
The patient might have multiple sclerosis.
The patient might have sickle cell anemia.
The patient might have serious vision problems.
The patient might have diabetes.

1. It takes Steve (or was it Ken?) 410 s to reach the store.

2. The whole trip takes Ken 1452 s.

3.  In minutes, the whole trip takes 24 min.

4. Ken travels 5 km during the whole trip.

5. The magnitude of Ken´s displacement is zero.

6. Since the displacement is equal to the null vector, it has no direction.

Explanation:

Hi there!

1. Using the equation of traveled distance, we can find the time it takes Ken to travel to the store:

D = v · t

Where:

D = traveled distance.

v = speed.

t = time.

Solving for t:

D/v = t

2500 m / 6.1 m/s = t

t = 410 s.

It takes Steve (or was it Ken?) 410 s to reach the store.

2. Let´s find how much time it takes Ken to return home using the same equation as in part 1:

D/v = t

2500 m / 2.4 m/s = t

t = 1042 s

Then, the whole trip takes Ken (1042 s + 410 s) 1452 s.

3. In minutes, the whole trip takes (1452 / 60 ) 24 min.

4. Ken travels 2.5 km to reach the store and 2.5 km to return home. So, he travels (2.5 km + 2.5 km) 5 km during the whole trip.

5. The displacement (Δx) is calculated as follows:

Δx = final position - initial position

If we consider his home as the origin of the frame of reference, the store will be located at 2.5 km to east (considered the positive direction).

Since the final position and the initial position are the same (the origin of the frame of reference), the displacement is zero:

Δx = final position - initial position = 0 - 0 = 0

Another way to see it:

The displacement of Ken to the store is 2.5 km east (positive). Then, the displacement is 2.5 km west (negative). Both displacement vectors have the same magnitude but opposite direction. So, the sum of both vectors is equal to the null vector. The magnitude of the null vector is zero.

6. Since the displacement is the null vector, it has no direction.