When light waves pass through the lenses of a pair of glasses the light waves

Write the function getkthdigit(n, k) that takes a possibly-negative int n and a non-negative int k, and returns the kth digit of n, starting from 0, counting from the right

Which is the correct symbol for an isotope of iodine with 53 protons and 78 neutrons?

Argon, neon, and xenon are examples of