What two systems work with the digestive system to control digestion speed? a. endocrine and excretory c. circulatory and nervous b. excretory and circulatory d. endocrine and circulatory select the best answer from the choices provided a b c d

true tan speed = ang vel x radius

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