You decide to study which dishwashing
detergent removes dried on ketchup
the fastest. Which of these would be
considered a constant in the
experiment?
A. Using different brands of dish detergent
B. Using different amounts of ketchup
The results show that the best way to remove stains is to use either a combination of vinegar and baking soda paste + commercial laundry detergent or to use a combination of commercial pre-stain treatment + laundry detergent.