Explanation:
First, we need to determine the distance traveled by the car in the first 30 minutes,
.
Notice that the unit measurement for speed, in this case, is km/hr. Thus, a unit conversion of from minutes into hours is required before proceeding with the calculation, as shown below

Now, it is known that the car traveled 40 km for the first 30 minutes. Hence, the remaining distance,
, in which the driver reduces the speed to 40km/hr is
.
Subsequently, we would also like to know the time taken for the car to reach its destination, denoted by
.
.
Finally, with all the required values at hand, the average speed of the car for the entire trip is calculated as the ratio of the change in distance over the change in time.

Therefore, the average speed of the car is 50 km/hr.
This is correct, I just did the test. Yes, displacement is 45 meters, elapsed time is three seconds, and the direction is toward the goal.
Answer:
0.176m from the flagpole, westward.
Explanation:
Let the Eastward be the positive direction. So initially runner A is at position -6km, running with velocity of 9km/h while runner B is at position 5km running at a velocity of -8km/h. We can conduct the following equation for their distances over the same time t


When A an B meets, they are at the same position and at the same time. So





So where they meet is 0.176m from the flagpole, westward.
Answer:
W = F * S = Newtons * Distance = Joules (definition)
Joules and KiloJoules are obviously methods of describing energy
F = M a = kg * m / s^2 definition of force
F * S = kg * m^2 / s^2 also describes work