What is seven and forty hundredths in standard form

The depth of a lake at a certain point, wich is a function of the distance of that point from shore, is 30 feet.

Brent wants to know what is 5 x 1/2

Let the closed interval [a , b] be the domain of function f. the domain of f(x - 3) is given by (a) the open interval (a , b) (b) the closed interval [a , b] (c) the closed interval [a - 3 , b - 3] (d) the closed interval [a + 3 , b + 3]