Answer:
The function that represents the mass of the sample after t days is
.
The percentage rate of change per hour is of -2.46%.
Step-by-step explanation:
Exponential amount of decay:
The exponential amount of decay for an amount of a substance after t days is given by:

In which A(0) is the initial amount, and r is the decay rate, as a decimal.
Element X is a radioactive isotope such that its mass decreases by 59% every day. The experiments starts out with 390 grams of Element X.
This means, respectively, that 
So



The function that represents the mass of the sample after t days is
.
Hourly rate of change:
Decreases by 59% every day, which means that for 24 hours, the rate of change is of -59%. So
-59%/24 = -2.46%
The percentage rate of change per hour is of -2.46%.
Is one of your options 240
Answer:
<em>Net price: $4972.50</em>
Step-by-step explanation:
<u>Percentages</u>
We know a ream of paper has a list price of $25.50. Custom Greetings placed an order for 300 of them. If they have purchased them at list price, the total price would have been
300*25.50=$7,650
But we also know there was a 35% trade discount, so the net price of their order is
$7,650-$7,650*35/100=$4972.50
<h3>
<u>Explanation</u></h3>

The structure or equation is similar to a quadratic function.
The value of a determines the slope of graph.
Tthe value of h determines the horizontal shift of graph.
The value of k determines the vertical shift of the graph.
From the given equation,

We can say that the graph shifts to the right 2 units and shifts down 7 units. Hence the vertex would be at x = 2 and y = -7. It can be written in coordinate form as (2,-7).
<h3>
<u>Answer</u></h3>
<u>
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