Time period of any moon of Jupiter is given by

from above formula we can say that mass of Jupiter is given by

now for part a)

T = 1.77 day = 152928 seconds
now by above formula



Part B)

T = 3.55 day = 306720 seconds
now by above formula



Part c)

T = 7.16 day = 618624 seconds
now by above formula



PART D)

T = 16.7 day = 1442880 seconds
now by above formula



Answer:
you divide the distance by the time it takes to travel that same distance, then you add your direction to it.
Answer:
If the line is curved, the slope is changing, which also means the velocity is changing. In a distance-time graph, the gradient of the line is equal to the speed of the object. The more the gradient (and the steeper the line) the faster the object is moving.