Estimate then find the product
12.32x9.75

You round up if the digit in the tenths if the digit is 5 or higher than 5. If any number that is lower you would round to zero. Do that for the one then the other.

So 12.32 is actually 12.00 in math terms

12.00x9.75 If there is a high number in the hundredths place then do the same thing with estimating.

9.75 is actually 10 in math terms.

So if 12.32x9.75 is actually 12x10 then the product is 120

Element 17 is chlorine it is a group 7 element(halogen) and belongs to period 3 of the periodic table