(3a) Some boats were traveling up and down a river. A satellite recorded the movements of several boats. A motor boat traveled -3.4 miles per hour for 0.75 hours. How far did it go?

(3b) Some boats were traveling up and down a river. A satellite recorded the movements of several boats. A tugboat traveled -1.5 miles in 0.3 hours. What was its velocity?

3a) 2.55 miles

3b) -5 mi/h

Step-by-step explanation:

3a)

In this problem, we want to know the distance travelled by the boat.

For a boat in uniform motion (=constant speed), the distance travelled can be written as

where:

d is the distance travelled

v is the speed

t is the time

For the motor boat in this problem, we have:

v = 3.4 mi/h (we ignore the negative sign, because it only refers to the direction, but here we are considering the speed, which is a scalar and has no direction)

t = 0.75 h is the time

Therefore, the distance travelled is

3b)

The velocity of an object is the ratio between its displacement (change in position) and time taken.

Since velocity is a vector, it has both a magnitude and a direction: so in this case, we also have to consider the sign when expressing the velocity.

The velocity is given by:

where

d is the displacement

t is the time taken

For the tugboat in this problem,

d = -1.5 mi is the displacement

t = 0.3 h is the time taken

So, its velocity is

And the negative sign indicates that the boat is moving in the negative direction.

depends on how many days you are talking about

step-by-step explanation:

circle area = pi * radius^2

if diameter = 10 then radius = 5

circle area = pi * 5^2

circle area = pi * 25

circle area = 78.5398163397 square units

step-by-step explanation: