An automobile weighing 2,000 lbs. is held stationary on a hill by its brakes.
The hill rises at an angle of 20°30'
with the horizontal. To hold back the
car, the brakes have to exert the same
force as would a cable fastened to one
end of the car and held by several men.
What is the strain, to the nearest
pound, imposed on the brakes?

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.