<u>Answer:</u> The element represented by M is Strontium.
<u>Explanation:</u>
Let us consider the molar mass of metal be 'x'.
The molar mass of MO will be = Molar mass of oxygen + Molar mass of metal = (16 + x)g/mol
It is given in the question that 15.44% of oxygen is present in metal oxide. So, the equation becomes:

The metal atom having molar mass as 87.62/mol is Strontium.
Hence, the element represented by M is Strontium.
Answer:
A:metal
Explanation:
because if a light bulb was placed on metal with force it would light
Zeff = Z - S
Here, Z is the number of protons in the nucleus, that is, atomic number, and S is the number of nonvalence electrons.
For boron, the electronic configuration is 1s₂ 2s₂ 2p₄
Z = 5, S = 2
Zeff = 5-2 = +3
For O, electronic configuration is 1s₂ 2s₂ 2p₄
Z = 8, S = 2
Zeff = 8-2 = +6
Hence, the correct answer is second option, that is, +3 and +6, the Zeff of boron is smaller in comparison to O, thus, boron exhibits a bigger size than O.
A incline plane is a flat inclined surface. You can stick a rope in the pulley and pull one side and the other side will lift something! They are both simple machines! The difference is a incline plane is a ramp and things go up or down and the pulley lifts something with force of your weight!!
Answer: -
71
Explanation: -
From the diagram, we see that volume goes from 70 to 75 in 5 markings.
Each marking is for 1.
It is the most accuracy possible as there is no smaller marking.
Significant figures expresses the required amount of accuracy.
Thus the volume indicated from the diagram is 71 .