  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.
Jupiters' atmosphere is composed of about 90% hydrogen and 10%  helium. There are only small traces of methane, ammonia, water and  rock dust (0.07%).Those traces give the â¦ Giant such grand colors.upiter's atmosphere is mainly Hydrogen (around 90%), Helium (around 10%), with small amounts (minor gases) of Methane (around 0.3% â¦), Ammonia (0.026%), Hydrogen Deuteride (0.003%), Ethane (0.0006%) and Water vapour (0.0004%).