Which of the following samples contain the greatest number of atoms? a. 2.0 mol of Ar (Argon)
b. 20 million of O2 (Oxygen) molecules
c. 5g of He (Hellium)
d. 100 g of Pb (Lead)​

Two friends at different locations want to communicate with each other by sending low energy signals. which of the following methods can they use to communicate? a) produce x-rays using colliding electrons and send them to radios, which capture sound b) send messages using infrared radiation, which travel in the form of waves c) send radio waves through intervening media like radio and television d) produce sound waves using microwaves from heated objects

Select the correct answer. which phrase correctly describes temperature? o a. average rotational kinetic energy of the particles in an object o b. average energy of the particles in an object c. average translational kinetic energy of the particles in an object od. all energy possessed by the particles in an object

Identify a specific example for each type of technology