Which equation illustrates the identity property of multiplication?
a)(a + bi) × c = (ac + bci)
b)(a + bi) × 0 = 0
c)(a + bi) × (c + di) = (c + di) × (a + bi)
d)(a + bi) × 1 = (a + bi)

Atextile fiber manufacturer is investigating a new drapery yarn, which the company claims has a mean thread elongation of 12 kilograms with a standard deviation of 0.5 kilograms. the company wishes to test the hypothesis upper h subscript 0 baseline colon mu equals 12 against upper h subscript 1 baseline colon mu less-than 12 using a random sample of n equals 4 specimens. calculate the p-value if the observed statistic is x overbar equals 11.8. round your final answer to five decimal places (e.g. 98.76543).

Collin did the work to see if 10 is a solution to the equation r/4=2.4

The equation of a parabola is given. y=18x2+4x+20 what are the coordinates of the focus of the parabola?