How many liters of water should be added to 20L of a 30% acid solution to make a solution that is 10% acid? ​

The answer is d angle 4

Standard form  is a way of writing down very large or very small numbers easily. 103  = 1000, so 4 × 103  = 4000 . so 4000 can be written as 4 × 10³ .hope this !