Scientist believe that the first life form appeared over how many years ago

Directions: Select each correct answer. More than one answer may be correct. It has been theorized that all of the modern continents on Earth were once part of a single continent. What scientific evidence is used to support this theory? A.

Most energy conversion processes are not efficient. True or False?

Which type of convergent boundary do you think will NOT have any deep ocean trenches? Continental/Continental Continental/Oceanic Oceanic/Oceanic

In 1665, what structures did Robert Hooke observe through a microscope?

Valence electrons are important because A) They form chemical bonds with other atoms B) They tell which period the element is in C) They take isotopes D) They identify the element

Which of these is an advantage of wind energy? A. It reduces bird and bat populations. B. It generates noise pollution. c. It generates electricity. D. It increases greenhouse gas emissions.

a group of of scientists is studying the internal parts of a cell. which microscope is most appropraite for these scientist to use

Which of the following choices is a biotic factor in the ecosystem? sunlight, water, deer, soil

Suppose that a given gene undergoes a mutation to its dominant allele such that two out of 100,000 offspring exhibit the new mutant phenotype. Assuming that these offspring are heterozygous, what is the mutation rate for the gene

A blood smear is used to diagnose malaria. In patients with malaria, the protozoa can be found near and inside red blood cells. Explain why a microscope capable of high magnification and high resolution would be meeded to diagnose malaria