Answer: 20 mg Te-99 remains after 12 hours.
Explanation: N(t) = N(0)*(1/2)^(t/t1/2)
N(t) = (80 mg)*(0.5)^(12/6)
N(t) = 20 mg remains after 12 hours
I don’t think there is another way for you to get an extra switch from your Xbox sorry:((
Answer:
According to the following position vs. Time graph the bicyclist was : D
D. Not moving for the first two seconds, then begin moving at the constant speed.
Explanation:

Along Y-axis = Distance in meters
Along X-axis = Time taken in second
- For first 2 seconds the The object has not changed its position.There is Zero distance covered.So , Speed = 0
- After 2 second,The Object changed the distance by equal amount in equal interval of time.(Uniform Speed).Hence at each point after 2 second, there is same value speed
<span>Evaporation from the oceans is the primary mechanism supporting the surface-to-atmosphere portion of the water cycle</span>
The volume of oxygen at STP required would be 252.0 mL.
<h3>Stoichiometic problem</h3>
The equation for the complete combustion of C2H2 is as below:

The mole ratio of C2H2 to O2 is 2:5.
1 mole of a gas at STP is 22.4 L.
At STP, 100.50 mL of C2H2 will be:
100.50 x 1/22400 = 0.0045 mole
Equivalent mole of O2 according to the balanced equation = 5/2 x 0.0045 = 0.01125 moles
0.01125 moles of O2 at STP = 0.01125 x 22400 = 252.0 mL
Thus, 252.0 mL of O2 gas will be required at STP.
More on stoichiometric problems can be found here: brainly.com/question/14465605
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