Is the set of monomials closed under addition? Which of the following gives a correct answer and an explanation?
A. Yes; the product of any two monomials is a monomial.
B. No; the sum of two monomials could be a polynomial.
C. Yes; the sum of any two monomials is a monomial.
D. No; the sum of two monomials could be a rational number.

Find the condition that the zeros of the polynomial f(x) = x^3+3px^2+3px+r may be in a.p.

Study results indicate that the mean length of time people spend on a bus in a city is between 21.2 min and 24.5 min what is the study margin of the error?

Agroup of student volunteers participates in a study designed to assess several behavioral interventions for improving output in a repetitive task. prior to the beginning of the study, all volunteers unknowingly observed, and their output is measured. at the beginning of the study, prior to any intervention, the volunteers perform the same task under the observation of a study administrator, and their overall output increases. which of the following terms describes this phenomenon? a. simpson's paradox b. hawthorne effect are d. novelty effect d. pygmalion effect e. observer-expectancy effect