If a=(-1,-3) and b=(11,-8), what is the length of ab

The denmark sound is a busy but water way

Solve for r in the formula v = ir, when i = 5 and v = 15.

Will give brainliest asaapppppppppppp plz im in a major hurry to finish which of these pairs of objects exerts the greatest gravitational force on each other? object 1 and object 3 object 4 and object 3 object 1 and object 4 object 4 and object 2