Answer: Potassium(K)
Explanation:
its an alkali metal placed under sodium and its over rubidium, its also the first element of period 4
Answer:

Explanation:
Given:
- mass of water,

- initial temperature of water,

- final temperature of water,

- specific heat of water,

<u>Now the amount of heat energy required:</u>



Since all of the mechanical energy is being converted into heat, therefore the same amount of mechanical energy is required.
Current will be

now just pluf in the values and Voila..
Gravity increased the downward speed (or decreases the upward speed) by 9.8 m/s every second.
21.2/9.8 = 2.2 seconds
<em>The </em><em>nucleus</em><em> has most of the atomic mass in an atom. The </em><em>nucleus</em><em> is made up of protons and neutrons.</em>
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