Explanation:
(a) Displacement of an object is the shortest path covered by it.
In this problem, a student is biking to school. She travels 0.7 km north, then realizes something has fallen out of her bag. She travels 0.3 km south to retrieve her item. She then travels 0.4 mi north to arrive at school.
0.4 miles = 0.64 km
displacement = 0.7-0.3+0.64 = 1.04 km
(b) Average velocity = total displacement/total time
t = 15 min = 0.25 hour

Hence, this is the required solution.
A couple things could be done such as recycling and using nonrenewable resources more efficiently.
The answer to this physics question would be 'a thin tungsten filament'. The element in an incandescent light bulb that releases light energy is a thin tungsten filament. All the other choices are not applicable as answers to this question.
Answer:
Before sled starts to move it has a potential energy due to the elevation...and then that potential energy converted to kinetic energy due to presence of a velocity...the sled will continue to move if their is no resesive force...but however friction force is presence that cause the sled to stop....
Answers:
a) 154.08 m/s=554.68 km/h
b) 108 m/s=388.8 km/h
Explanation:
<u>The complete question is written below:
</u>
<u></u>
<em>In 1977 off the coast of Australia, the fastest speed by a vessel on the water was achieved. If this vessel were to undergo an average acceleration of
, it would go from rest to its top speed in 85.6 s. </em>
<em>a) What was the speed of the vessel?
</em>
<em>
</em>
<em>b) If the vessel in the sample problem accelerates for 1.00 min, what will its speed be after that minute? </em>
<em></em>
<em>Calculate the answers in both meters per second and kilometers per hour</em>
<em></em>
a) The average acceleration
is expressed as:
(1)
Where:
is the variation of velocity in a given time
, which is the difference between the final velocity
and the initial velocity
(because it starts from rest).

Isolating
from (1):
(2)
(3)
(4)
If
and
then:
(4)
b) Now we need to find the final velocity when
:
<em></em>
(5)
(6)