Which represents newton's second law? a v=d/t b a=f/m c f=mv d f=0?

f=ma newton's second law 7x8=56n

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

not too sure thinking all accelerations are pointed down