A person can row 30 km downstream in 3 h and 54 km upstream in 9 h. Find the speed of the man in still water.

Isuck at math i am no sorry

Rain is pulled by gravity which is a non contact force

Answertraveling around a circular trackexplanation"traveling around a circular track" is the best answer as you could be traveling around a circular track at a constant speed. your velocity would therefore have the same magnitude but will always be constantly direction. since acceleration is the rate of change of velocity, the rate of change will only involve the direction of velocity and not the magnitude.wrong choices: "an object at rest" does not accelerate at all"increasing speed while traveling around a curve" means that the acceleration will not be constant due to only change in direction; it will be constant due to both magnitude and direction"an object in free fall" does not necessarily change direction 

If its history of, then b) because a) implies only present day (now)