CAN SOMEONE PLEASE HELP ME WITH THIS

Write the chemical symbols for three different atoms or atomic cations with 27 electrons. asap!

Each of the following reactions is allowed to come to equilibrium and then the volume is changed as indicated. predict the effect (shift right, shift left, or no effect) of the indicated volume change. drag the appropriate items to their respective bins.co(g) + h2o(g) < => co2(g) + h2(g) (volume is decreased) pcl3(g) + cl2(g) < => pcl5(g) (volume is increased) caco3(s)< => cao(s) + co2(g) (volume is increased)

When a device is used in a circuit in which the voltage is 81 v the current flowing through the device is 3 a what is the resistance of the device