The Symbol for a Certain Isotope of Strontium Is ${}^{90}_{38}$ SrWhat Is the Mass Number of This Isotope?
A)38
B)52

question 44

Multiple Choice

The symbol for a certain isotope of strontium is ${}^{90}_{38}$ Sr.What is the mass number of this isotope?

• A)38
• B)52
• C)88
• D)90
• E)128

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Definitions:

Cross Beds

Cross beds are sedimentary structures forming as inclined layers within horizontal units of sediment, often indicating the direction of ancient wind or water flows.

Sediment Deposition

The process by which sediment settles out of the water or air carrying it and is laid down in a new location.

Water Current

The directed movement of water, driven by various forces including wind, temperature differences, and gravitational effects, influencing marine and freshwater systems.

Sedimentary Rock

Rock formed by the deposition and subsequent cementation of mineral and organic particles on the earth's surface and within bodies of water.