Answer:
When her hands extends, her momen of inertia is
.
Explanation:
Given that,
Initial angular speed, 
Initial moment of inertia, 
Final angular speed, 
Initially, a skater rotates with her arms crossed and finally she extends her arms. The momentum remains conserved. Using the conservation of momentum as :

is final moment of inertia

So, when her hands extends, her momen of inertia is
. Hence, this is the required solution.
Entropy is the measure of the amount of disordered in a system.
<u>Explanation:</u>
In 1850, Entropy introduction by the German physicist Rudolf Clausius refers a measurement of the system's thermal energy in unit temperature. It is not for useful work because the work originates from ordered molecular motions. And, this also measures the molecular disturbance or randomness of the system.
The concept behind this provides deep view into spontaneous changes in many everyday phenomena’s. The idea of entropy is a mathematical way of coding an intuitive idea whose processes are impossible, and not violate the basic principle of energy conservation.
Mass- Mass is measured in kilograms (kg).
Weight- Weight is measured in Newton’s.
Answer:
The lethal voltage for the electrician under those conditions is 126.5 V.
Explanation:
To discover what is the lethal voltage to the electrician we need to find out what is the voltage that produces 55 mA = 0.055 A when across a resistance of 2300 Ohms (Electrician's body resistancy). For that we'll use Ohm's Law wich is expressed by the following equation:
V = i*R
Where V is the voltage we want to find out, i is the current wich is lethal to the electrician and R is his body resistance. By applying the given values we have:
V = 0.055*2300 = 126.5 V.
The lethal voltage for the electrician under those conditions is 126.5 V.