If you score a 100% on a test, explain what this means

it means ur a genius!!!

that means that u are the best and it's time to celebrate :):):):D:D:D:D:D:DD:D:D

Step-by-step explanation:

18.5 kilograms

Step-by-step explanation:

so first we can convert the values to have a common unit

so 4.5kg is also equal to 4500 grams

next we can find the mass of the 4 boxes

this can be modeled with the expression:

4*4500 which equals 18000

now we have to add the mass of the carton which is 500 grams

18000+500=18500

or 18.5 kilograms