Answer: 
Step-by-step explanation:
The midline of the function is

This means that to obtain a maximum of 10, when
reaches it's maximum, 1, 
Pretzels:2×200=400 200×1/2=100 100+400=500cups
Dry Cereal: 4×200=800 200×1/2=100 800+100=900cups
Peanuts:2×200=400 200×1/4=50 400+50=450cups
Raisins:200×3/4=150cups
6
The upside down U means intersection
A intersect B intersect C is where all 3 circles overlap.
Sum up all the numbers to get 50
P (a intersect b intersect c) = 6/50 = 3/25
Using the law os cosines formula b^2 = a^2 + c^2 - 2*a*c*cos(B)
a = 17, b = 8, c = 16
8^2 = 17^2 + 16^2 - 2*17*16* cos(B)
64 = 289 + 256 - 544 * cos(B)
544*cos(B) = 289 + 256 - 64
544 * cos(B) = 481
cos (B) = 481/544
B = arccos(481/544)
B = 27.8 degrees