Answer: Force
Explanation: Force is defined as a push or pull acting on an object
Explanation:
Speed: distance/time
Average speed: total distance/total time
Total distance: 400
Total time: 60
Average spead: 400/60= 6.67m/s
<u>Answer:</u>
1) Distance traveled by bird = 403 meter
2)Average speed = 1.66 km /hour
3) Zcceleration = 2 
<u>Explanation:</u>
1) Distance traveled = Speed * Time taken = 31 * 13 = 403 meter.
2) Average speed = Total distance covered / Time taken for that distance to cover.
Total distance covered = 2+0.5+2.5 = 5 km
Time taken = 3 hours
Average speed = 5/3 = 1.66 km /hour
3) Acceleration is defined as the rate of change of velocity, so acceleration a = change in velocity/time.
Change in velocity = 14 - 6 = 8 m/s
Time = 4 seconds
So acceleration = 8 / 4 = 2 
If the mass of the object and the volume of the object is determined;
Then, the density of the object is determined by taking the ratio of the mass and volume.
<h3>What is density of an object?</h3>
The density of an object is the ratio of the mass and volume of that object.
Mathematically;
To determine the density of an object therefore, the physical characteristics of mass and the volume of the object are measured.
The mass of the object is obtained using a scale or a balance.
The volume of the object if a solid is obtained using a displacement bottle. If it is a liquid, a measuring cylinder is used.
The density of the object is then obtained by taking the ratio of the mass and the volume of the object.
In conclusion, the density of an object is determined from the volume and mass ratio.
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