  Since 990 is divisible by ten, the answer is 990. If you were rounding off 994 the answer would also be 990. If you were rounding off 995, the answer would be 1,000.
Jupiter is the largest and most massive planet in the solar system. It was named after the chief Roman god. It is a gas giant composed of liquid and gaseous matter, and has many moons. Some of the storms in its atmosphere have lasted hundreds of years.
Scientists have defined the lower end of Jupiterâs atmosphere as the point where the pressure is 1 bar. Saturn is composed of mostly helium and hydrogen with traces of methane, ammonia, water ice, and other compounds. Saturnâs upper atmosphere is mostly ammonia crystals while the lower one is either water or ammonium hydrosulfide.