All of the following are true statements about harriet tubman except which one? a. she had been a slave. b. she left her husband to gain freedom. c. she was a conductor on the underground railroad. d. she wrote many books chronicling her experiences on the underground railroad.

Which suggests the most critical aspect of the peak oil theory? 1) controversy rages over rumors that the fracking lobby in washington has influenced the statistics. 2) supporters and critics argue endlessly over the rate of extraction and shape of the bell curve. 3) saudi arabia will soon have to begin fracking, leading to protests and further destabilization. 4) a new oil discovery means a fresh peak cycle, making that region the target of aggressors.