The spear is 4620 years old.
N=N0e^-kt
N0 = initial amount of C-14 (at time t = 0)
N = amount of C-14 at time t
t = time, in years
k = 0.0001
N/N0 = e^-kt
we know N/N0 is 0.63
so we have:
0.63 = e^-kt
we can take the ln of both sides, leaving us with:
ln0.63 = -kt
t = ln0.63 / -(0.0001)
t = 4620 years
hope this helps with your thing!
-keynerd23
Answer;
-Pumps require energy for transport because they move material against an electrochemical gradient, but channels and carriers do not use energy because they only facilitate diffusion down a molecule's or ion's electrochemical gradient.
Explanation;
-Permeability is conferred by two classes of membrane proteins, pumps and channels. Pumps use a source of free energy such as ATP or light to drive the thermodynamically uphill transport of ions or molecules. Pump action is an example of active transport.
-Channels, in contrast, enable ions to flow rapidly through membranes in a downhill direction. Channel action illustrates passive transport, or facilitated diffusion.
D. Photosynthesis only takes place in the light, while cellular respiration takes place in the light and dark.
A. "power plant" that provides energy for cells
The food we eat is brought to the mitochondria and broken down. Once it gets broken down the mitochondria converts the food into ATP
Hope this helped!
~Just a girl in love with Shawn Mendes
Answer:Connective tissue
Explanation: connective tissue are made up of a tissue consisting of living cells and a non-living substance. They are made up of collagen that are proteinous in nature.