Anurse is assessing the central venous pressure of a client who has a fluid imbalance. which reading would the nurse interpret as suggesting an ecf volume deficit

The normal pressure is approximately 4 to 11 cm H2O. ECF volume excess means that the pressure was increases, for example 12 cm H2O . A decrease in pressure, such as 3.5 cm H2O, on the other hand, may indicate an ECF volume deficit.

This is what i did 45-5=4040÷4=10so there are 10 white marbles but am not sure is just a question that am not sure