My mistake, yes one million.

Tell her a fun fact, in your best science teacher tone. It takes one billion microseconds to get to one second. Hopefully she can run with this and ask more questions.

Newer heat pumps are awesome. Northeast USA, with EcoEr brand. Two winters now close to single digits but rarely below freezing and it works like a charm. Mine is rated to operate to -40f. They had to wire it up for single heat source mode, by default they were wired for secondary heat source on the older models. Humidifier module can be added for winter comfort, my neighbor has that. Not sure what the cost tradeoff vs gas is, but it is definitely way cheaper than oil, which is what we replaced.

There are mini splits which require less construction, lower cost, with good cooling, but winter heat operating temp stops near 30f. Summer cooling feels like Arctic cold, and comes with built in dehumidifier for comfort. It definitely works harder to heat in winter than cooling in the summer.