YES, ELECTRICITY CONCERNS ENERGY WHICH IS USED AS A FUEL . IN MODERN DAY TECH, MOST MACHINES USE ELECTRICITY AS A FUEL SUCH AS THE ELECTRONIC TRAIN IN TOKYO, JAPAN.
Answer: The atomic mass of a Europium atom is 151.96445 amu.
From the given information:
Percent intensity is 91.61% of Europium atom of molecular weight 150.91986 amu.
Percent intensity is 100.00% of Europium atom of molecular weight 152.92138 amu.
Abundance of Eu-151 atom:

Abundance of Eu-153 atom:

Atomic mass of Europium atom:

Therefore, the atomic mass of a Europium atom is 151.96445 amu.
Answer:
t=1.623 sec
Explanation:
The distance traveled before the echo is had is:

Given the speed of sound as v=345m/s, we use the speed equation to solve for t:

Hence, it takes 1.623 seconds to hear the echo.
Answer:
True, the total amount of mechanical energy is merely the sum of the potential energy and the kinetic energy. This sum is simply referred to as the total mechanical energy.
Explanation: Hope it helps you:))))
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