1) The mass of the continent is 
2) The kinetic energy of the continent is 274.8 J
3) The speed of the jogger must be 2.76 m/s
Explanation:
1)
The continent is a slab of side 5900 km (so the surface is 5900 x 5900, assuming it is a square) and depth 26 km, therefore its volume is:

The mass of the continent is given by

where:
is its density
is its volume
Substituting, we find the mass:

2)
To find the kinetic energy, we need to convert the speed of the continent into m/s first.
The speed is
v = 1.6 cm/year
And we have:
1.6 cm = 0.016 m

So, the speed is

Now we can find the kinetic energy of the continent, which is given by

where
is the mass
is the speed
Substituting,

3)
The jogger in this part has the same kinetic energy of the continent, so
K = 274.8 J
And its mass is
m = 72 kg
We can write his kinetic energy as

where
v is the speed of the man
And solving the equation for v, we find his speed:

Learn more about kinetic energy:
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Almost true but not quite.
That would give you the negative of the actual acceleration.
It should be the other way around:
(final v) minus (initial v), then divide by time.
Taking into account the rule of three for the change of units, the mass of the book is 45600 miligrams.
First of all, the rule of three is a mathematical tool that helps you quickly solve proportionality problems.
Having three known values and one unknown, a proportional relationship is established between all of them in order to find the fourth term of the proportion.
If the relationship between the magnitudes is direct (when one magnitude increases, so does the other; or when one magnitude decreases, so does the other), the rule of three is applied as follows, where a, b and c are known values and x is the unknown to calculate:
a → b
c → x
So: 
Being 1 kg equivalent to 1000000 milligrams, In this case the rule of three is applied as follows: if 1 kg equals 1000000 milligrams, 4.56×10⁻² kg equals how many milligrams?
1 kg → 1000000 milligrams
4.56×10⁻² kg → x
So:

<u><em>x=45600 miligrams</em></u>
In summary, the mass of the book is 45600 miligrams.
Learn more:
Answer:
Synthesis reaction
Explanation:
Synthesis reaction: two or more compounds combine to form one.
A + B → C
Decomposition reaction: one compound forms two or more.
C → A + B
Single replacement reaction: an element in one compound is replaced with another element.
AB + C → AC + B
Double replacement reaction: elements in two compounds replace each other.
AB + CD → AC + BD
Pulling a dogs leash: inertia