Which two elements have similar properties and 8 electrons in their outermost shells? A. Chlorine and bromine
B. Calcium and strontium
C. Nitrogen and phosphorus
D. Argon and krypton
** THE ANSWER IS D **

Your target variable is δf, the magnitude of the difference in frequency between the waves emitted from the sonar device and the waves received by the device after reflecting off the whale. write an expression for δf in terms of the relevant frequencies using the subscript notation introduced above.

Several mountains together form a mountain . a few of these combined form a mountain system. several systems combined form a mountain , which can stretch thousands of miles in length.

What is a subatomic particle with a negative charge and very little mass?