What do an eye, a telescope, and a microscope have in common

Calculate - analysis of compound composed of iron and oxygen yields 174.86 of fe and 75.14g of o. what is the empirical formula for this compound?

Reactions in cells take place at about a. 40°c b. 0° c. 100°c d. 60°c

Animals that reproduce sexually either do it through external or internal fertilization. read the following statement and decide if it is true or false. birds reproduce through external reproduction which is because the female will then be able to protect the egg.