6. When humans first appear on Earth?

The covers all of earth like a thin shell,but it is not a solid sheet of material.it is broken up into several large sections and many smaller ones. fill in the blank.

Which of the following statements best describes the quantity theory of inflation? a.inflation occurs because production cost rise and this cost increase is passed on to consumers in the form of higher prices b. inflation occurs because there is too much money in the economy c. inflation occurs because demand of good and services exceeds existing supplies d. none of these

Which events occurred during the space race? check all that apply. (a) nasa was established. (b) yuri gagarin orbited earth. (c) the soviet union launched salyut. (d) the united states launched skylab. (e) the united states launched explorer 1.