Two students push on a car stuck in the mud with a force of 20 Newtons, 21
but they are unable to move it. How much work have they done?

A. O Joules

B.20 Joules

C.40 Joules

D. Not enough information given to answer this question.

Which sentence best describes the relationship between chlorophyll and the chloroplast? a.)chlorophyll is a chemical found in a chloroplast. b.) chloroplast is a chemical found in a chlorophyll. c.) both chlorophyll and chloroplasts are found in animals. d.) both chlorophyll and chloroplasts make carbon dioxide.

Archaebacteria use for movement. celia flagella pili cell walls

Which of the following explains why a tree is often used as a model to represent the principle of common descent