A manufacturer claims that a certain insulating material is good 'to keep the cold out'. Is this expression accurate? Plz explain using a diagram.
Plz tell it correctly .

The radioactive isotope of lead, pb-209, decays at a rate proportional to the amount present at time t and has a half-life of 3.3 hours. if 1 gram of this isotope is present initially, how long will it take for 80% of the lead to decay? (round your answer to two decimal places.)

Acircuit contain a 5-ohm, a3-ohm, and an 8-ohm resistor in series. what is the total resistance of the circuit

Describe the work performed by a ski lift in terms of kinetic and gravitational potential energy