A boat is heading due north across a river with a speed of 12.0 km/h relative to the water. The water in the river has a uniform velocity of 6.00 km/h due east relative to the ground. Determine the velocity of the boat relative to an observer standing on either bank.

Explanation:

Let speed of the boat in still water = u

speed of the river water = v

Relative speed of the boat in the water against the river flow is given by

Upstream speed = u - v ------- (1)

⇒ u - v = 12 ------ (2)

Given that speed of the water = 6

Now velocity of the boat is given From equation (2)

⇒ u = 12 + v

Put the value of v = 6 , we get

⇒ u = 12 + 6

⇒ u =  18

therefore , the velocity of the boat relative to an observer standing on either bank = u = 18

depends on what you mean by "group." for order, it would be coleoptera (beetles). for class, it would be insecta (insects). for phylum, it would be the arthropoda (animals with jointed exoskeletons).

explanation:

pythagoras' theorem

square root (-5^2+9^2)

square root (25+81)

square root (106)

angle is tan^-1(9/5)

neg x, pos y