Answer:
about 26 min
Step-by-step explanation:
Toni rows a boat 4.5 km/h upstream and then turns around and rows 5.5 km/h back downstream to her starting point
First we find the average speed
We add both speed and divide it by 2

Now we find the distance for round trip
given total time is 48 mins. convert mins into hours
48 mins = 48 divide by 60 = 0.8
average speed = 5 km/hr
Distance = speed * time = 5 * 0.8 = 4 km
distance covered both ways = 4 km
so 4 divide by 2 = 2 km each way
To find time taken for upstream = distance of each way / speed of upstream
time = 
Now convert hours into minutes
0.44* 60= 26.4 minutes
Answer:3/19
Step-by-step explanation:
5/19 - 2/19 = 3/19
Notice the picture below
negative angles, are just angles that go "clockwise", namely, the same direction a clock hands move hmmm so.... and one revolution is just 2π
now, you can have angles bigger than 2π of course, by simply keep going around, so, if you go around 3 times on the circle, say "counter-clockwise", or from right-to-left, counter as a clock goes, 3 times or 3 revolutions will give you an angle of 6π, because 2π+2π+2π is 6π
now... say... you have this angle here... let us find another that lands on that same spot
by simply just add 2π to it :)

now, that's a positive one
and

to get more, just keep on subtracting or adding 2π
Use the definition of tangent
or inv tangent (arctan or atan)
tan(theta) = opposite side/ adjacent side
the vertical rise would be the opposite side, the horozontal distance would be the adjacent side
let rise = y
let distance= x
x=2y
so tan(theta) = y/2y
tan(theta) = 1/2
theta = atan(1/2)
grab a handy dandy calculator, unless you know this conversion off the top of your head