Answer:
Step-by-step explanation:


Volume = 
find partial derivatives using product rule

i.e.
Using maximum for partial derivatives, we equate first partial derivative to 0.
y=0 or x+y =6
x=0 or x+4y =12
Simplify to get y =2, x = 4
thus critical points are (4,2) (6,0) (0,3)
Of these D the II derivative test gives
D<0 only for (4,2)
Hence maximum volume is when x=4, y=2, z= 4/3
Max volume is = 4(2)(4/3) = 32/3
Use dimensional analysis. 1 lb = 16 oz will be the conversion factor. 162 oz x (1 lb/16 oz) = 10.125 lb.

Let AB be a chord of the given circle with centre and radius 13 cm.
Then, OA = 13 cm and ab = 10 cm
From O, draw OL⊥ AB
We know that the perpendicular from the centre of a circle to a chord bisects the chord.
∴ AL = ½AB = (½ × 10)cm = 5 cm
From the right △OLA, we have
OA² = OL² + AL²
==> OL² = OA² – AL²
==> [(13)² – (5)²] cm² = 144cm²
==> OL = √144cm = 12 cm
Hence, the distance of the chord from the centre is 12 cm.
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Answer is a if I am not mistaken
He would use 9 bills, and 5 coins. (fours $10, one $5, four $1. three quarters, one dime, and one penny). I calculated it all to make sure the total came out as 49.86