An experiment was performed to compare the fracture toughness of high-purity 18 ni maraging steel with commercial-purity steel of the same type. for m = 30 specimens, the sample average toughness was x = 63.3 for the high-purity steel, whereas for n = 38 specimens of commercial steel y = 57.6. because the high-purity steel is more expensive, its use for a certain application can be justified only if its fracture toughness exceeds that of commercial-purity steel by more than 5. suppose that both toughness distributions are normal.

Date chapter motion and speed review part a. vocabulary review directions: write the terms that match each description below in thes complete the sentence in number 13. ich each description below in the spaces provided. the boxed letters will 1. equal forces acting in opposite directions (2 words) 2. occurs when an object's velocity decreases (2 words) 3. sum of all forces acting on an object (2 words) 4. total distance divided by total time (2 words) 5. name for the slant of a line on a graph 6. distance divided by time 7. a push or a pull exerted on a body or object 8. distance and direction of an object from its starting point 9. tendency to resist change in motion 10. measure of how far an object has moved 11. speed and direction of motion 12. rate of change of position at a specific point in time (2 words) 13. the rate of change in velocity is called motion and spe

How does the image distance (di) of a convex lens compare with the image distance of a concave lens? a. the image distance of the convex lens is positive, and that of the concave lens is negative. b. both are negative for a virtual image. c. both are positive for a virtual image d. the image distance of the convex lens is negative, and that of the concave lens is positive.

If an object with an initial temperature of 300 k increases its temperature by 1°c every minute, by how many degrees fahrenheit will its temperature have increased in 10 minutes? (a) 6°f (b) 10°f (c) 18°f (d) 30°f