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What tightening torque should be used for a hexagonal head screw (not split-bolt) on a 250 kcmil conductor?

Which of the following is a characteristic shared by both electron and light microscopes? a. they both employ the use of objective lenses. b. both microscopes require an internal camera to visualize the specimen. c. both microscopes have a resolving power of 0.01 nm. d. they both utilize white light to magnify the specimen.

The three classes of rocks are sedimentary, metamorphic, and igneous. how are rocks classified into one of these three groups?