apples are on sale for $3 and 12 per kilogram is the total cost of the apples proportional to the total yes or no

When you answer this can you explain

Use the following statements to write a compound statement for the conjunction or disjunction. then find its truth value. p: an isosceles triangle has two congruent sides. q: a right angle measures 90° r: four points are always coplanar. s: a decagon has 12 sides. a) a right angle measures 90° or an isosceles triangle has two congruent sides; true. b) a right angle measures 90° and an isosceles triangle has two congruent sides; true. c) a right angle measures 90° and an isosceles triangle does not have two congruent sides; false. d) a right angle measures 90° or an isosceles triangle does not have two congruent sides; true.

Simplify (8x2 − 1 + 2x3) − (7x3 − 3x2 + 1). −5x3 + 11x2 − 2 5x3 − 11x2 + 2 x3 + 2x2 + x3 x3 − 2x2 − x3