1. which pair of bacteria can be differentiated by oxidase test? A. Pseudomonas and E. coli
B. Salmonella and Proteus
C. Proteus and E. coli
D. Shigella and Salmonella

2. Colonies of which color would you expect on HE agar if shigellosis is suspected?
A. Pink
B. Red with black center
C. Red without black center
D. Green with black center
E. Green without black center

3. Colonies of which color would you expect on HE agar if Enterococcus sp. is suspected?
A. Pink
B. Salmon/orange
C. Red with black centers
D. Green with black centers
E. None of the above

1. A. Pseudomonas and E. coli

2. B. Red without black center

3. B. Salmon/orange

Explanation:

Pseudomonas is referred to as an oxidase positive bacteria while E. Coli is an oxidase negative bacteria. The use of the oxidase test will be helpful in the differentiation of the two Bacteria according to their oxidase activity/properties.

Colonies of Red without black center color is what is expected on HE agar if shigellosis is suspected.

Colonies of Salmon/Orange color is what is expected on HE agar if Enterococcus sp. is suspected.

satellites are frequently used to make observations of the orbit on earth

c. earths continental crust is thicker than its lithosphere.

because, the lithosphere is the outermost layer of the earth/ 100 km thick and is defined by its machanical properties.the lithosphere contains oceanic and continental crust that varies in age and thickness across locations and geologic time. the lithosphere is the coolest layer of the earth in terms of temperature. the term lithosphere should not be confused with the use of "geosphere" which is used to indicate all of earth systems, including the atmosphere, hydrosphere   and biosphere. the surface of the earth can be divided into the continental crust and the oceanic crust.   the continental crust is made mostly of granite while the oceanic crust is made of basalt. the average thickness of the continental crust is 25 miles and the average thickness of the oceanic crust is 5 miles.   three types of rock, igneous, sedimentary, and metamorphic, make up the surface of the earth. that's why 3 option is preferable.