An object is dropped from the top of a cliff 610 meters high. Its height above the ground t seconds after it is dropped is 610 - 4.9t. Determine its speed 2 seconds after it is dropped. The speed of the object 2 seconds after it is dropped is m/sec. (Simplify your answer.)Write the function below in the form y = f(u) and u = g(x), then find dy as a function of x. dx y = (7x - 18)4 Write y = (7x - 18)" in the form y = f(u) and u = g(x). Choose the correct functions f(u) and g(x) below. O A. f(u) = 7u-18 O B. f ( u ) = Tut g(x) = x# g(X) = X- 18 O C. f ( u ) = ( u - 18) # O D. f (u ) = u# g(x) = 7x - 18 g(x) = 7x