Vlass 2. The SI unit for mass is the kilogram, however we will use the in our science class to make measurements, because it is more appropriate for measuring the mass of small objects. c) milligram d) liter a) centimeter b) gram.​

the only real purpose of sputnik 1 was to beat the us into space. we were getting close to launching a useful satellite, explorer 1 - which launched on january 31, 1958. the ussr had to beat that, so they launched sputnik 1 on october 4, 19

one "light year" is the distance that light travels, through vacuum, in one julian year.   that's 365.25 days, of 24 hours each.