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:
Acceleration is a derived unit because it is derived from two quantities : Velocity and time.
We know, acceleration = Change in velocity/Time
Answer: <span>D. A bimetallic strip bends so that the steel is on the outside curve
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When something has an increased temperature, its volume will expand. Then, if the temperature drops, its volume should be smaller. From there option A and B are out since the liquid in thermometer is expand or move up.
When you put two kinds of different metal with a different coefficient of thermal expansion, the outer curve metal will be the one with lesser coefficient when temperature drop. Since the question about drop in temperature then the metal should be bend
Brass will expand 1.5 times more than the steel so the outer curve would be the steel.
The correct answer is
<span>c the friction force from the road
In fact, the friction force between the road and the tires prevents the car from "sliding away" in a straight line and keeps it in circular motion, acting as centripetal force.</span>