What things did the Europeans discover about the natural world from their explorations? Biology question Help asap plz

At which location in earth’s interior does the top density continue to increase as thickness decreases?

What is required in the genotype of an individual to show a recessive trait? a. two recessive alleles b. at least one recessive allele c. no recessive alleles

An uncomfortable feeling in the ears when descending in an airplane is caused by changes in air pressure on the: a. inner ear b. middle ear c. eardrum d. hammer/anvil