(a) We must prove the following expression that if A |=taut B and C |=taut D then A ∨ C |=taut B ∨ D. (b) Show that the formulas A ≡ ⊥ and ¬A are tautologically equivalent?

$4034.40

the perimeter of the field is the sum of the lengths of the four sides:

47 yd + 158 yd + 47 yd + 158 yd = 410 yd

the cost of 3 ft (1 yd) of fence is 3×$3.28 = $9.84.

so the cost of jake's wood perimeter fance is

(410 yd) × ($9.84 /yd) = $4034.40

think the answer is 30 degrees. if not than it is 20 degrees. not 100% sure. let me know if it was right.

gill russ