1-explain what causes the seasons ?

2- defined and provide examples of each of the following poikilotherm, homeotherm, endotherm, and ectotherm ?

3- how climate processes ( temperature and precipitation) result in the location of the biomes. for instance how hadley cells create deserts at 30 degree latitude.

Ashould be answer.

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

Ones bigger then than the other

Temperature, rainfall and relative humidity.