Answer:
3,432 m²
Step-by-step explanation:
The amount of aluminum in square meters needed to make the mailboxes = 1863(surface area of each mailbox)
Surface area of each mail box = ½(surface area of cylinder) + (Surface area of rectangular prism/box - area of the surface of the box that joins the half-cylinder)
✔️Surface area of ½-cylinder = ½[2πr(h + r)]
r = ½(0.4) = 0.2 m
h = 0.6 m
π = 3.14
Surface area of ½-cylinder = ½[2*3.14*0.2(0.6 + 0.2]
= 0.628(0.8)
Surface area of ½-cylinder = 0.5024 m²
✔️Surface area of the rectangular box/prism = 2(LW + LH + WH)
L = 0.6 m
W = 0.4 m
H = 0.55 m
Surface area = 2(0.6*0.4 + 0.6*0.55 + 0.4*0.55)
Surface area of rectangular box = 1.58 m²
✔️Area of the surface joining the half cylinder and the box = L*W = 0.6*0.4 = 0.24 m²
✅Surface area of 1 mailbox = (0.5024) + (1.58 - 0.24)
= 0.5024 + 1.34
= 1.8424
Amount of aluminum needed to make 1863 mailboxes = 1863 × 1.8424 = 3,432.3912
= 3,432 m²
Answer:
Step-by-step explanation:
The Pascal triangle is used to determine the coefficients of the terms when we expand the expression.
1
= 1
1 1 
1 2 1 
By extending the triangle, you will get the 9th row, which is your expression, of the coefficients. that is
1 9 36 84 126 126 84 36 9 1
Now, fill in AB in the gaps.
1AB + 9 AB + 36AB + 84AB + 126AB + 126AB +84AB + 36AB + 9AB + 1AB
Next, you need to go from the left to fill out the exponent of A and it will go down from 9 (the exponent of the whole thing) . That is

Next will be the exponent of B. this time, you go from the right and do the same with A. You can go from the left also, but go up from 0 to 9 for the exponent of B

The last step is just to simplify the A^0=1 and B^0 =1 at the first and the last terms.

Hope you can learn the method
So c-9 is less than or equal to 20 so c is less than or equal to 29. So the correct answer is c. Hope this helps :)
Answer:
L = ∫₀²ᵖⁱ √((1 − sin t)² + (1 − cos t)²) dt
Step-by-step explanation:
Arc length of a parametric curve is:
L = ∫ₐᵇ √((dx/dt)² + (dy/dt)²) dt
x = t + cos t, dx/dt = 1 − sin t
y = t − sin t, dy/dt = 1 − cos t
L = ∫₀²ᵖⁱ √((1 − sin t)² + (1 − cos t)²) dt
Or, if you wish to simplify:
L = ∫₀²ᵖⁱ √(1 − 2 sin t + sin²t + 1 − 2 cos t + cos²t) dt
L = ∫₀²ᵖⁱ √(3 − 2 sin t − 2 cos t) dt