Record the temperature shown on the thermometer to the nearest half of a degree.

The thermometer shows a temperature of °C.

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

Iknow #2 is d. i just need to know why

How many moles of al3+ ions are in 1.25 moles of al2o3