How do scientists know that the universe is expanding?
1. The Doppler effect shows stars with yellow shifted light
2. The Doppler effect shows stars with green shifted light
3.The Doppler effect shows stars with blue shifted light
4. The Doppler effect shows stars with red shifted light
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What type of link is

The us is first  the  u.s. economy  remains the  largest in the world  in terms of nominal  gdp. however, the  u.s. economy  loses its spot as the number one  economy  to china when  measured  in terms of  gdp  based on ppp. in these terms, china's  gdp  is $23.19 trillion exceeds the  u.s. gdp  of $19.42 trillion

When the indian plate collided with eurasian plate because it was cool 

Answer music,television, corn,soybean