Answer:
680
Explanation:
When the P680 special pair of photosystem II absorbs energy, it enters an excited (high-energy) state. Excited P680 is a good electron donor and can transfer its excited electron to the primary electron acceptor, pheophytin.
The appropriate answer is A. the density of ice would be greater than the density of liquid water and so ice would not float. Density can be defined as mass per unit volume. Any substance whose mass is great and occupies a relatively small volume is going to be dense.
Water expands by nine to ten percent when it freezes and this expansion increases the space occupied or the volume and so the density of ice is less than water.
Answer:
The North American and Eurasian Plates are moving away from each other along the line of the Mid Atlantic Ridge. The Ridge extends into the South Atlantic Ocean between the South American and African Plates.