Answer:
I think the answer is C.
Explanation:
A primary source is a first hand account of an event while a secondary source is a retelling or second hand account meaning as many details will be prevalent.
Recall that

where
and
are the initial and final velocities, respecitvely;
is the acceleration; and
is the change in position.
So we have


(Normally, this equation has two solutions, but we omit the negative one because the car is moving in one direction.)
Answer:
38.3 m/s
Explanation:
To find vertical component of initial velocity, you'd have to use sine ratio:

is vertical component of initial velocity and
is initial velocity given which is 50 m/s.
A stone is projected at an angle of 50 degrees so
= 50°. Substitute in the formula:

Therefore, the vertical component of initial velocity is approximately 38.3 m/s
(The picture is also attached for visual reference!)
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.
The formula is:
Work = Force · Displacement
F = m · g
F = 16 kg · 9.8 m/s² = 156.8 N
and we know that:
d = 0.8 m
W = 156.8 N · 0.8 m = 125.44 J
Answer:
W = 125.44 J.