Hello there!
I can help you out with #15 to help get you started/ unstuck! :)
So I see you have your conversion table drawn! Fantastic!
So you start off by putting the GIVEN unit in the first (top) space.
12 g
Next, you put " 1 g " ( 1 gram ) below, and to the right of it. (Diagonal right 1 block).
Why 1 gram? Because the units g will cancel each other out!
So on the box NEXT to your 12 g, put ___kg. This will give you your new unit.
For now, you can search up how many kilograms there are in a gram but it'll be very helpful in the future to have it memorized. :)
Clarification:
"How many kg are there in a g?"
We do this because the bottom says " 1 gram," so since we're converting grams to kilograms, we're converting 1 gram to ___ kilograms.
After filling out your chart, multiply the tops together! Cancel out units, and use a calculator if it's allowed! :)
Summary:
1). Make an empty conversion table.
2). Start with the given unit in the top left space.
3). Move down, and to the right: Put 1 (unit). This will cancel the units out later.
4). Above the 1 (unit), put (???) (new unit).
To find (???) simply search it up. :)
Ex). "How many kg are there in 1 g?"
The units should cancel out on their own. :)
With this, it simply takes practice. I'm sure you'll get the hang of it in no time! :D
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DISCLAIMER: I am not a professional tutor or have any professional background in your subject. Please do not copy my work down, as that will only make things harder for you in the long run. Take the time to really understand this, and it'll make future problems easier. I am human, and may make mistakes, despite my best efforts. Again, I possess no professional background in your subject, so anything you do with my help will be your responsibility. Thank you for reading this, and have a wonderful day/night!