The equation h(t)=−16t2+19t+110 gives the height of a rock, in feet, t seconds after it is thrown from a cliff. what is the initial velocity when the rock is thrown?

For this case we have an equation of the form:
 h (t) = (1/2) at2 + vot + h0
 Where:
 a: acceleration
 vo: initial speed.
 h0: initial height
 Substituting values we have:
 h (t) = - 16t2 + 19t + 110
 The initial speed is then:
 vo = 19 feet / s
 
 The initial velocity when the rock is thrown is:
 vo = 19 feet / s

Iwould think that the correct answer is 8.1