Answer:
- 17. A. 180 in²
- 18. B. 234 in²
Step-by-step explanation:
#17
<u>Total surface area is:</u>
- A = 8(3*2 + 6*2) + 2(3*6) = 180 in²
Correct option is A
#18
<u>Total surface area is:</u>
- A = 2(9*9) + 4(2*9) = 234 in²
Correct option is B
Answer:
Bottom left
Step-by-step explanation:
Because when you draw the graph you see that x is larger than 2 , and 2 is not including in the solution so, we just make a small lines (forget the y-axis).
I hope that it's a clear solution and explanation.
Answer:
i)W = 2500 / T
ii) W = 500 Tons
iii) grad W(10°) = - 25î
iv) The formulation is not practical
Step-by-step explanation:
i) Write an equation describing the use of coal
As use of coal is inversely proportional to the average monthly temperature
if W is use of coal in tons/per month then
W(t) = k / T where k is a constant of proportionality and T is the average temperature in degrees. We have to determine k from given conditions
k = ?? we know that when T = 25° W = 100 tons the by subtitution
W = k/T 100 = k /25 k = 2500 Tons*degree
Then final equation is:
W = 2500 / T
ii) Find the amount of coal when T = 5 degrees
W = 2500 / 5
W = 500 Tons
iii)
The inverse proportionality implies that W will decrease as T increase.
The vector gradient of W function is:
grad W = DW(t)/dt î
grad W = - 2500/T² î
Wich agrees with the fact that W is decreasing.
And when T = 100°
grad W(10°) = - 2500/ 100 î ⇒ grad W(10°) = - 25î
iv) When T = 0 The quantity of coal tends to infinite and the previous formulation is not practical
(a.) is the answr. ............................................
