A scientist is using a microscope to observe a type of bacteria.
Which two structures would the scientist most likely see?
nucleus and DNA
O DNA and cell wall
O cell wall and vacuole
vacuole and nucleus

15. which of the following is not human-caused groundwater pollution? a. water in an aquifer dissolves elements such as arsenic and mercury from surrounding rock. b. water in an aquifer is contaminated by leachate that seeps into the ground from a landfill. c. water in an aquifer becomes polluted with chemicals used in hydraulic fracturing, or fracking. d. water in an aquifer absorbs harmful bacteria from the drainage field of a septic tank.

Covalent compounds: mastery test select the correct answer what is formed when atoms join together with a covalent bond? a. an ion b. a molecule c. a neutral atom d. a noble gas

Lord kelvin described the concept of absolute zero temperature and the laws relating to the change of thermal energy during chemical reactions what type of chemist would he be considered today