I was able to find 10 endangered species. And they are:
Kings Gold its a plant.
Delta Smelt its a fish
Amargosa vole it is a critter either a rat or a mouse.
Tricolored blackbird it is a type of a song bird.
Buena Vista Lake ornate shrew it is a type of mouse or rat
Desert Slender Salamande it is a reptile. type of lizard
Lange's metalmark butterfly
Sacramento river winter-run Chinook salmon it is a type of fish
California condor it is a type of bird
Gray wolf
Hope this helped
After two half-lives or 60 years, 7.5 g of the element will be left.
<u>Explanation:</u>
<u>Half-life:</u>
- In simple words, Half-life can be defined as the amount of time needed for a quantity to fall to half its value as contained at the beginning of the time period.
- In this problem the half-life of the element is thirty years, then after thirty years half of the sample would have decayed and half would be left as it is.
- After thirty years (The first half-life ) 30 /2 = 15 g declines and 15 g remains disappeared.
- And after another sixty years (The two half-lives) 15 /2 = 7.5 g declines and 7.5 g remains disappeared.
- After two half-lives or 60 years, 7.5 g of the element will be left.