7. A hummingbird, with an initial velocity of 12.0 m/s [N], flies 450 m [N] to the next flower, along a straight line with constant acceleration, in 25.0 s. The acceleration of the hummingbird during this time, in scientific notation, is a.bc x 10-d mis. The values for a, b, c, and d, respectively, are and (Record all four digits of your answer.)