Which of the following is an example of a longitudinal wave? A. A wave traveling down a long, stretched string, with both ends held
fixed.
B. A wave on the surface of a drum that has been struck.
C. A wave traveling down a stretched Slinky toy, with both ends held
fixed.
D. A wave of ocean water as it reaches the beach.

the answer would be c

because natural gas is colorless, odorless, and tasteless, distributors add mercaptan (a chemical that smells like sulfur) to give natural gas a distinct unpleasant odor (it smells like rotten eggs). they locate the types of rock that are likely to contain natural gas deposits.

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.