Scientists can determine the age of ancient objects by a method called radiocarbon dating. The bombardment of the upper atmosphere by cosmic rays converts bitrogen to a radioactive isotope of carbon, C-14, with a half life of about 5730 years. Vegetation absorbs carbon dioxide through the atmosphere and animal life assimilates C-14 through food chains. When a plant or animal dies it stops replacing its carbon and the amount of C-14 begins to decrease through radioactive decay. Therefore, the level of radioactivity must also exponentially decay. A parchment fragment was discovered that had about 74% as much C-14 radioactivity as does plant material on the earth today. Estimate the age of the parchment.

a

explanation:

the answer is (-4,-4)

hope this ! : d

2. angles qrt and qst both measures 156 degrees.

step-by-step explanation:  

we have been given a diagram of a circle and we are told that measure of arc qvt is 156 degrees.  

we can see from our given diagram that angle qrt and angle qst subtends to arc qvt.

since we know that angles subtended by the same arc at the circumference are always equal.

by angle subtended by same arc theorem, measure of angle qrt and angle qst will be equal to the measure of arc qvt.

therefore, angles qrt and qst both measures 156 degrees and 2nd statement is the correct choice.

step-by-step explanation:

f(x)=2x^2 -1 

translation is a function transformation that transform the function in a way of translating. by translating the function its graph is moved  up an down. moving the function f(x) 2 units to the left will be the new function g(x) with the equation: g(x)=f(x+2)=2(x+2)^2 -1