Vihaan finds that the roots of a quadratic equation that contains a difference of squares pattern is x = +-16. What is true about the graph of the parabola described by the quadratic equation? The graph contains two parabolas: one that touches the x-axis at x = 16 and one that touches the x-axis at x = -16.
The parabola crosses the x-axis at x = +-16.
The graph contains a parabola that does not have a vertex.
The parabola does not touch or cross the axis.

Arandomized controlled trial is designed to evaluate the effect of metoprolol in patients with heart failure. while preparing for statistical analysis, the researcher reviews some common types of statistical errors. which of the following statements is true regarding a type i error in a clinical study? a. the study is not significantly powered to detect a true difference between study groups. bthe null hypothesis is true but is rejected in error. c. the null hypothesis is false but is accepted in error. d. type i error is also known as beta and is usually 0.1 or 0.2. e. type i error depends on the study's confidence interval.