Hello! Please help me to anser these physics questions.
1] calculate the power dissipated by a heater of 220V and a resistance of 10ohms.

2] Calculate the energy in a lamp with a resistance of 40ohms when a current of 5 amperes passes through it in 150seconds.


3] A wire of 40cm long and diameter o.60mm has a resistance of 1.5ohms what is the resistivity of the material of which it is made (n=3.142).

4] Calculate the distance of separation between two electrons (in vacuum) for which the electric force between them is equal to the gravitational force on one of them at the earth surface charge of electron = 1.6*10-19C, mass of electron 9.1*10-31kg, g= 1.0m/s2.