Pls explain this in a easy way so my teacher ain’t sus

Answer:
Binh is correct
Step-by-step explanation:
This because when multiplying any number by 10^2 it just means that's how many times the decmial point is moving. In this case when multiply by 10^2 the decimal only moves twice so when you multiply 10^2 by 0.4 the decimal moves twice which eqauls 40.