According to Cennini, an artist should use layers of gesso, and they should be burnished until they appear like . a. nine; bronze b. ten; ivory c. seven; ivory d. eleven; bronze

Layer r contains a well-known index fossil that is 100 million years old. based on this information and the principle of superposition, a. layers t and m are older than 100 million years, and layers x and g are younger than 100 million years. b. layers t, m, x, and g are all older than 100 million years. c. layers t and m are younger than 100 million years, and layers x and g are older than 100 million years.