en el simulador phet en la construcción del átomo estable de berilio, el átomo quedo de la siguiente manera: 4 protones, 4 electrones y 5 neutrones. ¿cuál será su numero de masa (a)?

Mount saint helen the great lakes and death valley are physical features of the earth which scientific term describes these features

Name and describe how to implement one method of embellishment.

Scientists observed a rock stratum and discovered some fossils. the image shows the fossils they discovered. what can you interpret from the image? an illustration showing layers rock with fossils embedded in some rock layers1. the dinosaur and the mammoth existed after the trilobites.2. the dinosaur and the armored fish existed before the trilobites.3. the trilobites and the armored fish died before the dinosaur.4. the trilobites and the armored fish were born after the dinosaur.5. the early mammoth is older than the trilobites.