A large number in front of a compound designates how many units there are of that compound. Parentheses can be used to designate a special structure, where other molecules are attached to the larger, complex molecule.
About 255.3 grams is the answer I believe. I just had a school work packet and had that question on it, and that is the answer that I had put on it I believe.
Here is how i made slime when i had a buisiness.
Add glue to a bowl.
13 pumps of foaming hand soap
a table spoon of cornstarch
coloring
borax
add everything but borax and stir! then slowly add borax and knead until it is at your desired texture :D
0.005 is the correct answer i hope this helps man :)