Why is price descrimination not possible under perfect market conditions??​

In its 2016 annual report, caterpillar inc. reported the following (in millions): 2016 2015 sales $38,537 $47,011 cost of goods sold 28,309 33,546 as a percentage of sales, did caterpillar's gross profit increase or decrease during 2016? select one: a. gross profit increased from 26.8% to 28.6% b. gross profit decreased from 28.6% to 26.5% c. gross profit increased from 71.4% to 73.2% d. gross profit decreased from 73.2% to 71.4% e. there is not enough information to answer the question.

How did the contribution of the goods producing sector to gdp growth change between 2010 and 2011 a. it fell by 0.3%. b. it fell by 2.3%. c. it rose by 2.3%. d. it rose by 0.6%. the answer is b

Find the zeros of the polynomial 5 x square + 12 x + 7 by factorization method and verify the relation between zeros and coefficient of the polynomials