Question

please give answer of this question​

Answer 1

we know that

sin(180- x) = sin x

therefore sin (150) = sin(180-30)

= 30

= 1/2

Answer 2

Explanation:

Atomic number of oxygen is 8.

It means, Oxygen will have 8 protons and 8 electrons. Atomic number = Number of Protons = Number of electrons.

Atomic mass of oxygen is 16u.

So, Number of neutrons = Atomic mass - Number of protons = 16 - 8 = 8

So, Oxygen contains 8 protons, 8 neutrons and 8 electrons.

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Atomic number of nitrogen is 7

It means, Nitrogen will have 7 protons and 7 electrons. Atomic number = Number of Protons = Number of electrons.

Atomic mass of nitrogen is 15u.

So, Number of neutrons = Atomic mass - Number of protons = 15 - 7 = 8

So, Nitrogen contains 7 protons, 8 neutrons and 7 electrons.

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Atomic number of sodium is 11

It means, Sodium will have 11 protons and 11 electrons. Atomic number = Number of Protons = Number of electrons.

Atomic mass of sodium is 23u.

So, Number of neutrons = Atomic mass - Number of protons = 23 - 11 = 12

So, Sodium contains 11 protons, 12 neutrons and 11 electrons.

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Atomic number of fluorine is 9

It means, fluorine will have 9 protons and 9 electrons. Atomic number = Number of Protons = Number of electrons.

Atomic mass of fluorine is 19u.

So, Number of neutrons = Atomic mass - Number of protons = 19 - 9 = 10

So, Fluorine contains 9 protons, 10 neutrons and 9 electrons.Atomic number of fluorine is 9

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Atomic number of chlorine is 17

It means, chlorine will have 17 protons and 17 electrons. Atomic number = Number of Protons = Number of electrons.

Atomic mass of chlorine is 35u.

So, Number of neutrons = Atomic mass - Number of protons = 35 - 17 = 18.

So, Chlorine contains 17 protons, 18 neutrons and 17 electrons.

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Atomic number of calcium is 20

It means, calcium will have 20 protons and 20 electrons. Atomic number = Number of Protons = Number of electrons.

Atomic mass of calcium is 40u.

So, Number of neutrons = Atomic mass - Number of protons = 40 - 20 = 20.

So, Calcium contains 20 protons, 20 neutrons and 20 electrons.

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Atomic number of sodium is 11

It means, Sodium will have 11 protons and 11 electrons. Atomic number = Number of Protons = Number of electrons.

Atomic mass of sodium is 23u.

So, Number of neutrons = Atomic mass - Number of protons = 23 - 11 = 12

So, Sodium contains 11 protons, 12 neutrons and 11 electrons.

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Atomic number of Pottasium is 19

It means, Pottasium will have 19 protons and 19 electrons. Atomic number = Number of Protons = Number of electrons.

Atomic number of Pottasium is 39u.

So, Number of neutrons = Atomic mass - Number of protons = 39 - 19 = 20

So, Pottasium contains 19 protons, 20 neutrons and 19 electrons.

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BY USING THE ABOVE PROCEDURE YOU CAN YOU CALCULATE BY YOURSELF.

I can't type anymore.

HOPE IT HELPS.