In an island ecosystem, fox and skunks both hunt mice and toads. which of the following correctly describes some of these relationships?
a) skunks and mice have a competitive relationship.
b) skunks and toads have a predator-prey relationship.
c) fox and stuff have a predator-prey relationship.
d) toads and mice have a competitive relationship.

Asnail, elodea (aquatic plant), or both were added to the tubes and they were stoppered. tubes were placed under a grow light for 24 hours and the results recorded. the test tubes were then covered for 24 hours to produce a dark environment and the results recorded. which statement best explains the change in test tube d from the light setup to the dark setup.

Hemoglobin is the compound in red blood cells that carries oxygen to the body. the distribution of hemoglobin in women in g/dl of blood is approximately normally distributed with mean 14 and standard deviation 1. too little hemoglobin, and you're anemic. 2. too much, and (unless you live at high altitudes), you can have other problems.

What percentage of light hits earth's surface directly?