a) Sea Level = Neither positve nor negative
This is because sea level has zero value and zero is neither a positive nor negative number.
b) Receives = Positive
c) Sells = Positive
d) Deduct = negative
e) Credit = negative
f) debit = positive
g) Above sea level = Positive
h) Gain = positive
i) Buy = negative
j) Ground level = Neither positive nor negative
