I Place a 500-G Ice Cube (Initially at 0 $\degree$ C)in a Styrofoam Box with Wall Thickness 1

question 7

Multiple Choice

I place a 500-g ice cube (initially at 0 $\degree$ C) in a Styrofoam box with wall thickness 1.0 cm and total surface area 600 cm².If the air surrounding the box is at 20 $\degree$ C and after 4 hours the ice is completely melted,what is the conductivity of the Styrofoam material? (L_f = 80 cal/g)

• A)9.6 x 10^-5 cal/s*cm* \(\degree\)C
• B)2.8 x 10^-6 cal/s*cm* \(\degree\)C
• C)1.15 x 10^-2 cal/s*cm* \(\degree\)C
• D)2.3 x 10^-4 cal/s*cm* \(\degree\)C

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Definitions:

Accounts Receivable

Money owed to a company by its customers for goods or services that have been delivered or used but not yet paid for.

Collection Period

The time frame it takes for a business to convert its credit sales into cash, reflecting how efficient a company is at collecting accounts receivable.

Net Present Value

The difference between the present value of cash inflows and the present value of cash outflows over a period of time. It is used to evaluate the profitability of an investment or project.

Default Rate

The proportion of loans or debt instruments that are not repaid as agreed, leading to default, within a specific period.