Answer:
it takes longer for the boat to get back because it's moving against the current. to see how fast the boat is moving, you divide the amount of miles traveled, by how long it took.
240/20 = 12
in still water the boat travels it's 12 miles per hour
240/ 60 = 4
against the current, the boat travels 4 miles per hour
if you need to find the speed of the current, you need to find the resistance that's going against the boat making it slow down. you do that by doing 12 - 4 = 8 miles per hour is the speed of the current.
Step-by-step explanation:
I hope this helps :)
Answer:
B AND F
Step-by-step explanation:
!!!!!!!!
The first thing we should do is write the functions.
For the area we have:
A = w * h = 20000 feet ^ 2
The price is:
Cost = (4 * 2 * h + 2 * 2 * w)
Substitute for h ::
C (w) = (4 * 2 * (20,000 / w) + 2 * 2w)
Rewrite we have:
C (w) = 160,000 / w + 4w
Take the derivative:
C '(w) = 160000 (-1 / w ^ 2) + 4
We equal zero and clear w:
0 = 160000 (-1 / w ^ 2) + 4
160000 / w ^ 2 = 4
w ^ 2 = 40000
w = 200 (approximately)
width = 200 ft; so cost is 2 * ($ 4) 200 = $ 1600
height = 20000/200 = 100 ft; so cost is 2 ($ 2) 100 = $ 400
Total cost = $ 2000
Answer:
The cost of the least expensive fence is:
Total cost = $ 2000
12.) This does not follow the rule of conservation because on the reactant side there is one Na and two Cl while the product side only has one Na and Cl. They are not equal and do not have the same number of atoms for the different elements. In the law of conservation matter cannot be created or destroyed and this does not follow the law.
13.) 2Na + Cl2 —> 2NaCl
Put a 2 in front of Na and a 2 in front of NaCl
Answer:
it is 20
Step-by-step explanation:
12-8=4 so we add the 4 to the 12 and it gives us 16...then 16 rounded off to the nearest 10 is 20