S = d/t
st = d
t = d/s
The time going is t1.
The time returning is t2.
The total time is 4 hours, so we have t1 + t2 = 4
The speed of the current is c.
The speed going is 9 + c.
The speed returning is 9 - c.
t1 = 16/(9 + c)
t2 = 16/(9 - c)
t1 + t2 = 16/(9 + c) + 16/(9 - c)
4 = 16/(9 - c) + 16/(9 + c)
1 = 4/(9 - c) + 4/(9 + c)
(9 + c)(9 - c) = 4(9 - c) + 4(9 + c)
81 - c^2 = 36 - 4c + 36 + 4c
81 - c^2 = 72
c^2 = 9
c^2 - 9 = 0
(c + 3)(c - 3) = 0
c + 3 = 0 or c - 3 = 0
c = -3 or c = 3
We discard the negative answer, and we get c = 3.
The speed of the current is 3 mph.
Answer:
Mass of gold bar = 13.896 kg
Step-by-step explanation:
Volume of gold bar = Area of trapezium x Length of bar
Length of bar = 16 cm
Area of trapezium = 2 x Area of triangle + Area of rectangle
Area of triangle = 0.5 x 5 x 3 = 7.5 cm²
2 x Area of triangle = 2 x 7.5 = 15 cm²
Area of rectangle = 6 x 5 = 30 cm²
Area of trapezium = 15 + 30 = 45 cm²
Volume of gold bar = 45 x 16 = 720 cm³
Density of gold = 19.3 g/cm³
Mass of gold bar = 720 x 19.3 = 13896 g = 13.896 kg
Mass of gold bar = 13.896 kg
The graph is missing, so i have attached it.
Answer:
From 0 hours to 2 hours.
Step-by-step explanation:
From the attached graph, we can see that on the y-axis, denotes the level of ibuprofen in the patient’s bloodstream while the x-axis denotes the amount of hours after the ibuprofen was taken.
Now, looking at the graph, we can see that the curve goes up from a time of 0 hours which corresponds to 0 mg of ibuprofen to a time of 2 hours which corresponds to 400 mg of ibuprofen.
After that point, the curve begins to to go down. Since we are concerned with increase, we will make do with the first statement.
Thus, we can say the period at which the level of ibuprofen increased was from 0 hours to 2 hours.
