Which expressions are equivalent to 7b(3+c)

An objects motion is described by the equation d= 4sin (pi t) what will the height of the object be at 1.75 seconds?

Bob is putting books on a shelf and takes a break after filling 18 1/2 inches on the book shelf. the book shelf is now 2/3 full. how long is the entire bookshelf?

Two years ago a man was six times as old as his daughter. in 18 years he will be twice as old as his daughter. determine their present ages.