Explanation:
my guess
its +2 because NO3 has a 2 next to it
also other side of the equation Cl has a 2 next to it
(~26grams/mole) and Avogadros # (6.022x10^23) 84.3grams x 1mole/26grams x 6.022x10^23 molecules/mole = 1.95x10^24 molecules of C2H2
The 10% rule means that approximately there will be only 10% energy transferred from a trophic level into another. That was because the consumer on the upper level will use the energy before it was consumed. About 90% of the energy used so only 10% remain will be transferred.
Example: an antler eating grass with a total 100 calories. Then the antler is moving and growing, using 90 calories. Then a lion eats the antler, but the energy remains is only 10 calorie because 90 calories are already used.
I'm not sure but it should be 7.31 times 2 times 3.14 or pi
7.31 x 2 x 3.14 = 45.9068
If you need to round to the nearest tenth it will be 45.9
If you need to round to the nearest hundredth it will be 45.91
