<h3><u><em>
Answer:</em></u></h3><h3><u><em>
30</em></u></h3><h3><u><em>
Step-by-step explanation:</em></u></h3><h3><u><em>
Answer: 30 gallons</em></u></h3><h3><u><em>
</em></u></h3><h3><u><em>
Step-by-step explanation:</em></u></h3><h3><u><em>
</em></u></h3><h3><u><em>
So fist we add 40% and $40%. That's 80 percent of the tank which is 12 + 12 = 24. </em></u></h3><h3><u><em>
Then we figure out half of 40 percent which is 20 which means its 6 gallons. </em></u></h3><h3><u><em>
Now we add. 12+12+6 which equals our answer 30 gallons</em></u></h3><h3><u><em>
</em></u></h3>
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Theres only 4 but the answer is -15
Answer:
Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g
Please give brainliest
First add 15$ then add $1,245 all together as it says and it should give u the answer