Answer:
It will take 15.029 years for element X to reach mass of 260 grams
Step-by-step explanation:
The half life period of radioactive element X is 26 years
The initial mass of radioactive element X is 260 grams
Elapsed time = half life * log (beginning amount /ending amount)/log 2
Substituting the given values, we get
Elapsed time = 26 * log (390/260)/log 2
= 15.209 years
Combine like terms then you have your answers
Answer:C) x2 + y2 =45
Step-by-step explanation:
The equation of a circle in standard form is (x-h)2+(y-k)2=r2.
Since you know the center is (0,0), you can sub this is value in for h and k, then use the point (3,6) to sub in for x and y and you will find r2 =45. Hope that helps :)
Black line (a) -
x = -2
Purple line (b) -
x = 3
Blue line (c) -
y = 6
Green line (d) -
y = -3
Red line (e) -
Not sure
