Which of the following is not one of da vinci's contributions to technology?
a. effect of the moon on tides
b. modern theory on the formations of the continents
c. precise observations of human anatomy
d. ideas for space travel

An experiment was performed on a 2-kg block. forces of 5, 10 and 15 newtons respectively were applied to the block for 5 seconds. describe the difference in acceleration between the three trials. a) the final accelerations will all be the same. b) the final acceleration will triple between the first and third trial. c) the final acceleration will be cut by 1/3 from the first to third trial. d) the final acceleration will increase nine time between the first and third trial.