7 5/21 I think that would be the one that can cover it but not have to much left.
You might need a second opinion.
2 4/10
2 2/5
That's the answer
Step-by-step explanation:
(a) P = (0.3)(0.2) + (0.5)(0.6) + (0.2)(0.8)
P = 0.52
(b) (0.5)(0.6) = 0.3
P = 0.3 / 0.52
P = 0.58
P(t)=500(1+4t/(50+t^2 ))
P'(t) = 500 [(50+t^2).4 - 4t.2t]/(50+t^2)^2
by the quotient rule
500 (-4t^2 + 200)/(t^2 + 50)^2
Hence
P'(2) = 500 . (-16 + 200)/54^2 ~= 31.6
the process is coal formation which changes into fossil fuels through burning
