Choose all of the equations that represent a parabola with the focus (0,4) and the vertex (0, -6). A. x2 = 20 (y + 1)
B. x2 = 40 (y + 6)
O c. 20y = x2 - 20
D. 40y = (x + 6)2
E. 40y = x2 - 240

The standard form of the equation of a circumference is given by the following expression:

 (x-h)2 + (y-k)2 + r2

54 kilometers per hour

step-by-step explanation:

according to rules:

1 km = 1000 meter

which means that 1 meter = 1/1000 km

1 hour = 3600 second [ as 1 hour = 60 min = 60 *60 seconds ]

which means that 1 second = 1/3600 hour

therefore, 1 kilometer/hour =

thus to convert 15 meter per second to kilometer per hour, we multiply 15 to 3.6 kilometer/hour.

15 meter/second=   which is the required answer.