The valves of the heart and veins are similar in that they both: A.) Prevent blood from flowing too quickly.

B.) Are made of rigid cartilage.

C.) Prevent backflow of blood.

D.) Act as propellers to move blood forward.

Aknife blade is a(n) a. lever b. screw c. wedge d. inclined plane

The force acting on a beam was measured under the same operating conditions and a sample of 5 data points was collected. this process was repeated by 3 observers. the pooled standard deviations of these 3 data sets was 1.21. determine the true mean force using all pooled data (with a 95% probability). the result should look like this: true mean = mean +/- margin of error

Which sound characteristic is not affected by the relative motion of an object