I see trees of green Red roses too
I see them bloom
For me and you
And I think to myself
What a wonderful world

I see skies of blue
And clouds of white
The bright blessed day
The dark sacred night
And I think to myself
What a wonderful world

The colors of the rainbow
So pretty in the sky
Are also on the faces
Of people going by
I see friends shaking hands
Saying, "How do you do?"
They're really saying
"I love you"

I hear babies cry
I watch them grow
They'll learn much more
Than I'll never know
And I think to myself
What a wonderful world

Yes, I think to myself
What a wonderful world

okkgreat

Deep. Respect.

Explanation:

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.