Pl HELP ill mark Brainliest to who helps +20 pts

Find the maximum and minimum values of the objective function f(x, y) and for what values of x and y they occur, subject to the given constraints.
f(x, y) = 2x + 6y
x ≥ 0
y ≥ 0
2x + 7y ≤ 70
8x + 4y ≤ 136

a. max at (14,6)=64, min at (0,0)=0
b. max at (15,9)= 84, min at (0,0)=0
c. max at (0,10)=60, min at (0,0)=0
d. max at (17,0)=34, min at (0,0)=0

C. is not the answer

To complete your spring schedule, you must add calculus and physics. at 9: 30, there are three calculus sections and two physics sections; while at 11: 30, there are two calculus sections and three physics sections. how many ways can you complete your schedule if your only open periods are 9: 30 and 11: 30?

Suppose there is a simple index of three stocks, stock abc, stock xyz, and stock qrs. stock abc opens on day 1 with 4000 shares at $3.15 per share. stock xyz opens on day 1 with 5000 shares at $4.30 per share. stock qrs opens on day 1 with 6000 shares at $4.60 per share. the price of stock abc on day 8 begins at $3.50. the price of stock xyz on day 8 begins at $3.90. stock qrs opens on day 8 with a price of $4.50 per share. assume that each stock has the same number of shares that it opened with on day 1. what is the rate of change of this simple index over 1 week?

Abcd is a parallelogram find the valuse of x