Difference between plant cell and animal cell?

Plz fast biotechnology is a growing field of applied biology. many crops such as corn have been engineered to be resistant to herbicides. therefore farmers can spray these chemicals to kill weeds growing near the crop without worries of killing the crop itself how does this type of biotechnology work? a. by changing the genetic make up of the crops. b. by causing the crops to kill the weeds. c. by changing the type of crops used. d. by changing the location of the crops.

The cretaceous period spanned the time interval between and 65 million years ago. 250 million 144 million 75 million 200 million

Archeologists have discovered three sites showing conclusive evidence for the mastery of fire in tanzania, from a period slightly after the time that homo habilis was present in africa. these sites clearly were founded by homo erectus, the descendent species of homo habilis that migrated north, out of africa and into asia. homo erectus was known to have mastered fire, from ample evidence at sites in asia. there is no reason to attribute mastery of fire to homo ergaster, the descendent species of homo habilis that remained in africa.which of the following is an assumption on which the argument depends? (a) before their migration, homo erectus occupied african territory as far south as tanzania.(b) the strain of migration provided the selective pressure motivating homo erectus‘ mastery of fire.(c) homo ergaster would not have derived as much benefit from the mastery of fire as did homo erectus.(d) homo ergaster inherited all cultural knowledge from homo habilis, a species that did not have mastery of fire.(e) homo ergaster did not occupy regions as far south as tanzania until well after the time of these three sites.