Answer:
A) A(t) = 4500*π - 1600*t
B) A(4) = 7730 in³
C) t = 8,8 sec
Step-by-step explanation:
The volume of the sphere is:
d max = 30 r max = 15 in
V(s) = (4/3)*π*r³ V(s) = (4/3)*π* (15)³
V(s) = 4500*π
A) Amount of air needed to fill the ball A(t)
A(t) = Total max. volume of the sphere - rate of flux of air * time
A(t) = 4500*π - 1600*t in³
B) After 4 minutes
A(4) = 4500*π - 6400
A(4) = 14130 - 6400
A(4) = 7730 in³
C) A(t) = 4500*π - 1600*t
when A(t) = 0 the ball got its maximum volume then:
4500*π - 1600*t = 0
t = 14130/1600
t = 8,8 sec
Your answer would look like this
I assume you meant "surface area" :)
Looking at the net, it looks like if you folded it back together it would form to become a triangular prism.
To calculate the surface area of a triangular prism, you would use the formula: A = bh + 2ls + lb, where b is the base of the triangular faces, h is the height of the prism, l is the length of the prism, and s is the side length of the prism.
I attached a picture to help you see what these labels are.
Looking at the diagram you've provided, we can assume that b = 7 cm, h = 4 cm, l = 8 cm, and s = 5 cm. Substitute these into the formula.
A = bh + 2ls + lb ==> A = (7)(4) + 2(8)(5) + (8)(7)
Multiply from left to right.
28 + 80 + 56
Add.
164
The surface area of this triangular prism is A) 164 cm^2.