Answer:
The speed of the boat in still water is 18 mph.
The speed of the current is 2 mph
Step-by-step explanation:
Let x represent the speed of the boat in still water.
Let y represent the speed of the current.
When the boat goes against the current, the speed is 16 mph. Assuming it traveled against the current while going upstream, its total speed would be (x - y) mph. It means that
x - y = 16 (equation 1)
Going downstream, the boat averages 20 mph. Assuming it traveled with the current, its total speed would be (x + y) mph. It means that
x + y = 20 (equation 2)
Adding both equations, it becomes
2x = 36
x = 36/2
x = 18 mph
Substituting x = 18 into equation 1, it becomes
18 - y = 16
y = 18 - 16
y = 2 mph
Answer:
A) B is greater
B) when C = 21, A = 5 and B = 15
C) A must be 0, 5, or 12 for C to be greater than B
Step-by-step explanation:
A) when a = -3, c = -20 and b = 4(-3)-5 so B = -17
B) when c = 21, a = 5 and b = 4(5)-5 so B = 15
C) C is greater than B when a = 0, 5, and 12
when a = 0, b = 4(0)-5 or -5
when a = 5, b = 4(5)-5 or 15
when a = 12, b = 4(12)-5 or 43
Answer:
Radius of sphere is 3 units.
Step-by-step explanation:
Volume of sphere is given by 
surface area of sphere is given by 
where r is the radius of the sphere.
Given that
The number of cubic units in the volume of a sphere is equal to the number of square units in the surface area of the sphere.
we equate formula of Volume of sphere and surface area of sphere
assuming r as the radius.
thus,

Thus, radius of sphere is 3 units.