6. Which of the following quadratic equation canbe easily solved by extracting the square roots? aligned 21=0\\ ;=0 aligned a. x ^ 2 - 4x - 21 = 0 b. 4x ^ 2 - 25 = 0 c. 3x ^ 2 - 6x - 21 = 0 d. x ^ 2 + 9x + 18 = 0

What are potential hypotheses (explanations) regarding why there are ecological equivalents between many metatherians and eutherians? discuss your hypothesis in terms of the processes that could lead to the current ecologies and distributions of metatherians and eutherians.

William invested $5000 in an account that earns 3.8% interest, compounded annually. the formula for compound interest is a(t) = p(1 + i)t. how much did william have in the account after 6 years? (apex)

In a survey of 1015 adults, a polling agency asked, "when you retire, do you think you will have enough money to live comfortably or not. of the 1015 surveyed, 534 stated that they were worried about having enough money to live comfortably in retirement. construct a 90% confidence interval for the proportion of adults who are worried about having enough money to live comfortably in retirement.