A trilobite. Trilobites became extinct about 250 million years ago while a ammonite became extinct around the same time as dinosaurs(65 million years ago). You wouldn't find a human skull or a dinosaur footprint
4. Cinder cones are a volcano
The correct answer is A. grass
A mold was developing in some of the culture dishes used by Sir Alexander Fleming and was eliminating some of the bacterial population. The hypothesis is that the mold was generating a chemical, which was toxic to the bacteria in the dishes and killed them.
The hypothesis was examined by separating the Penicillium and administering it into the solution of nutrient broth. After the growth of Penicillium it was withdrawn from the broth. The broth was then eventually supplemented to the bacteria and the bacteria died. Thus, it can be concluded that the hypothesis is supported.
