The X can possibly be the sex chromosome. Like for human female we have the XX chromosomes and when the allele is on the X chromosome we write as X with a R as the superscript on top right.
There's 2 in the first energy level
Which leaves 2 left to go in the second level
Btw the second level can normally hold a max of 8
I think C because in order to tell what the age is it depends on the depth of it like fossils the deeper the older it gets Soo if I dug a tunnel 25 meters deep I could be able to tell the age and if u dug a little bit more u can maybe fine dinosaur bones that and the ground and sea ground can change or shift from place to place. I hope u found this a reasonable answer for u.
Answer:
Change a light. Replacing one regular light bulb with a compact fluorescent light bulb will save 150 pounds of carbon dioxide a year.
Drive less. Walk, bike, carpool or take mass transit more often. ...
Recycle more. ...
Check your tires. ...
Use less hot water. ...
Avoid products with a lot of packaging. ...
Adjust your thermostat. ...
Plant a tree.
Explanation:
