What moon phase occurs 3-4 days after a waning gibbous?

The waning gibbous phase is the phase between the full and last quarter moon late at night or in the early morning . The waning crescent is the phase that occurs 3-4 days later a waning gibbous.

The waning gibbous phase is the phase between the full and last quarter moon late at night or in the early morning.

The waning gibbous phase moon appears more than half-lighted but less than the full moon. A full sunset is a time when the full moon rises. The rising time of the waning gibbous moon is late at night.

It looks red like a  full moon when it’s near the horizon.

To learn more about the waning gibbous refer to the link ;

link

The "waning gibbous" begins immediately after the Full Moon and lasts about a week.

At the end of the week, the moon is no longer gibbous, but it's still waning.  At the instant it's exactly half-illuminated, it's called "Third Quarter", and then it continuous to wane for another week.

So 3 to 4 days after the END of the waning gibbous phase, it's a Waning Crescent. It still has another 3 to 4 days of waning to go, before it wanes away to nothing and we have the next New Moon.

20000 pounds

Explanation:

Generally 1 gallon of fuel burnt gives of 20 pounds of CO₂

Difference in the gallons of fuel burnt

The 20 mpg car burns 1000 gallons of fuel more than the 30 mpg car

The amount of CO₂ would be

The fewer pounds that the 30 mpg car would release is 20000 pounds