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.
In terms of function, bird wings are used to flap transversely, whereas butterfly wings are used to flap laterally. In terms of structure, bird wings are filled with hollow bones for easier flight, whereas butterfly wings are structured by scales and tiny hairs.
Answer:
independent variable: the different amount of water
Explanation:
The independent variable would be the <u>different amount of water supplied to the pea plant clones.</u>
<em>The independent variable is the variable inputted by the researcher during an experiment whose value directly affects the dependent variable. It is the variable that is manipulated during experiments in order to see the kind of effects they produce on another variable - the dependent variable.</em>
In this case, <u>the amount of water supplied to each pea plant would directly affect the height of the pea plants.</u> Hence, the amount of water supplied to the pea plants is the independent variable while the height of the plants is the dependent variable.
Nucleotides - they are molecules present in cells and are formed by nitrogenous bases