No planet that we know of has only 2.7 hours of daylight - the rotational period of the fastest planet in our solar system is 9 hours 55 minutes (for Jupiter).
The planet Uranus occupies an orbit at about 2.7 light hours distance (about 2 hours 40 minutes) from the Sun - but its distance does not affect how many hours of daylight it receives, since it is constantly illuminated regardless of its spin. An observer on Uranus would see a somewhat strange day, owing to its axial tilt - the planet orbits "on its side" - the observer might see the sun for half of its year at a time, in a spiral path around its daytime sky.
11 hours
That depends entirely on what time of year it is - as would be the case anywhere else on the planet.
A day on Mars is a bit longer than on Earth - 24 hours, 39 minutes, 35 seconds. So, just as the length of daylight on Earth depends on (a) the seasons, and (b) the latitude of the location in question, so a random place on Mars would have a varied range of possible length of daylight. If you know what part of the planet you need to know about then you can probably compare it easily with the earth - allowing for the angle the planet's rotation makes with the Sun.
I think there is around 18 hours of daylight!
A Guide for the Daylight Hours was created in 2002.
September 21st is the Autumnal equinox, and everywhere on the planet (except the exact poles) has 12 hours of day and 12 hours of night.
4
The Northern Hemisphere has the most hours of daylight during the summer solstice, which occurs around June 21st each year. Areas near the Arctic Circle, such as parts of Scandinavia, experience nearly 24 hours of daylight during this time.
Uranus
There are about 8.5 hours of daylight at the start of November and about 9 hours at the end of February, but on the winter solstice (around December 21-22), there is about 7 hours and 52 minutes of daylight.
That would depend on where in the world you are. If you were at the North Pole there would be 24 hours of daylight, while at the South Pole there would be no daylight. At points in between the two poles the amount of daylight would be different. At the equator the amount of daylight hours would be about 12 hours.
6 hours