What causes thunder?
a. static electricity in the air
b. the sudden heating of the air by a lightning bolt
c. the movement of raindrops and hail within the cloud
d. the formation of raindrops out of rapidly condensing water vapor?

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

A47.2 g block of copper whose temperature is 480 k is placed in an insulating box with a 91.8 g block of lead whose temperature is 200 k. (a) what is the equilibrium temperature of the two-block system? (b) what is the change in the internal energy of the two-block system between the initial state and the equilibrium state? (c) what is the change in the entropy of the two-block system? the heat capacities of copper and lead are 386 j/kg·k and 128 j/kg·k, respectively.

State the below theories and give the name of the writer of the theory 1. wave theory 2. quantum theory 3. corpuscular theory 4. electromagnetic theory