(02.04 MC) Kris spends every day of the summer swimming in the lake behind her grandparent's house. By the end of the summer, she is having daily dizzy spells, migraine
headaches, and nausea. What can Kris infer about the possible source and reason for her illness?
It is an acute effect of a toxin in the lake

Which mantle is under the crust the upper mantle or the lower mantle i think it's upper let me know if i'm right

Iron reacts with oxygen to produce iron oxide (rust). this reaction is represented in an equation as 4fe + xo2 → 2fe2o3. identify the value of x that will balance the equation.

Up until 1938, paleontologists accepted the idea that coelacanths (an ancient fish) went extinct at the time that they last appear in the fossil record, about 80 million years ago. but in 1938, a live coelacanth was discovered off the coast of south africa that was compared to the fossil record and found to be the same species what goal of science does this discovery represent