Answer:
Rock
Explanation:
Minerals are inorganic substances that occur naturally in nature and have a
a definite chemical composition and a crystalline structure while rocks may consists of one or many minerals together along with some organic remains due to which it may not look shiny and crystalline from outside.
Here, the two characteristics that enable the reader to identify the object given by grandmother to Emily as rock are –
a) Looks ugly on the outside (shows the presence of organic matter)
b) solid purple color with pretty crystals (crystalline structure inside)
B la patogenicidad de un virus
Bacterial infections were much harder to treat a long time ago because we didn't have the same technology or information that we do now. because we have worked so long on treating different things we have learned what works and what doesnt. the new technology has helped us understand the infection which led to us being able to find medication to treat said infection.
Answer:
In uranium-lead dating, for instance, the radioactive decay of uranium into lead proceeds at a reliable rate. Based on the very old zircon rock from Australia we know that the Earth is at least 4.374 billion years old.
And that's how after rounding we know that earth is 4.5 years old.
