Rubidium-87 Decays by Beta Decay with a Half-Life of 4

question 57

Multiple Choice

Rubidium-87 decays by beta decay with a half-life of 4.9 * 10¹⁰ yr. How many ⁸⁷Rb atoms are in a moon rock sample that has a rubidium decay rate of 3,500 disintegrations per hour

• A) 9.0 * 10¹⁶ atoms
• B) 4.3 * 10^-4 atoms
• C) 2.2 * 10¹⁸ atoms
• D) 2.5 * 10¹⁴ atoms
• E) 1.7 * 10¹⁴ atoms

Apply flexible budget principles to forecast costs and income under varying production levels.

Understand the relationship between fixed costs, variable costs, and production volume in financial planning.

Understand and calculate direct labor efficiency variance.

Calculate and analyze direct labor rate variance.

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Definitions:

Products

In a chemical reaction, substances that are formed as a result of the reaction.

Primary Mycelium

A mycelium in which the cells are monokaryotic and haploid; a mycelium that grows from either an ascospore or a basidiospore. Compare with secondary mycelium.

Basidiomycetes

A class of fungi characterized by producing spores on club-shaped structures called basidia, including mushrooms, toadstools, and puffballs.

Dikaryotic

Describing a fungal cell or mycelium with two genetically distinct nuclei per cell, typically found in the life cycle of fungi.