Aradar astronomer who is new at the job claims she beamed radio waves to jupiter and received an echo exactly 48 min later. should you believe her? why or why not?

Should not believe her because the time taken is too short.

Explanation:

Time taken for echo to reach Earth = 48 min

Time taken by radio wave to reach Jupiter = 24 min

Distance between Earth and Jupiter when closest = 588 million kilometers = 588×10⁹ m

Distance between Earth and Jupiter when farthest = 968 million kilometers = 968×10⁹ m

Speed of radio wave = Speed of light = 3×10⁸ m/s

Distance = Velocity × Time

⇒Distance = 3×10⁸×24×60

⇒Distance = 432×10⁹ m

Which does not fall under the range of distance of Jupiter. So, I should not believe her.

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

causes

fossil fuels burn

cities become more industrialized

human population grows worldwide