10. In a port fuel-injected engine, shorter runners yield A. increased high-RPM power.
B. minimum low-RPM power.
C. increased low-RPM power.
D. minimum high-RPM power.

Thermal stresses are developed in a metal when its a) initial temperature is changed b) final temperature is changed c) density is changed d) thermal deformation is prevented e) expansion is prevented f) contraction is prevented

Asolid cylinder is concentric with a straight pipe. the cylinder is 0.5 m long and has an outside diameter of 8 cm. the pipe has an inside diameter of 8.5 cm. the annulus between the cylinder ad the pipe contains stationary oil. the oil has a specific gravity of 0.92 and a kinematic viscosity of 5.57 x 10-4 m2/s. most nearly, what is the force needed to move the cylinder along the pipe at a constant velocity of 1 m/s?

What is the heat treatment of metals? what is the benefit of it? why and how it's useful? answer in details, do not write by hand.