Answer:
1) $350
2) 55°
3) $300
Step-by-step explanation:
1) The total cost is the cost of the appointment plus the cost of the repair work. The appointment costs $50. The repair work costs $120 per 2 hours. So the total cost is:
C = 50 + (120/2) t
C = 50 + 60t
For 5 hours of work, the cost is:
C = 50 + 60(5)
C = 350
It costs $350.
2) The temperature starts at 70°. It drops 10° in 4 hours. So the temperature after t hours is:
T = 70 + (-10/4) t
T = 70 − 2.5t
After 6 hours:
T = 70 − 2.5(6)
T = 55
The temperature is 55°.
3) Jennie's total pay is her weekly pay plus her commissions. If her commission is x% of her sales, then her pay is:
P = 250 + (x/100) S
When her sales is $1000, her pay is $275.
275 = 250 + (x/100) 1000
275 = 250 + 10x
25 = 10x
x = 2.5
So her pay is:
P = 250 + (2.5/100) S
When S = $2000:
P = 250 + (2.5/100) 2000
P = 250 + 50
P = 300
Her total pay is $300.
(2√5 + 3(√7))^2
(2√5 + 3(√7))(2√5 + 3(√7))
4*5 + 6√35 + 6√35 + 9*7
20 + 12√35 + 63
20 + 63 + 12√35
83 + 12√35
Answer:
1/3
Step-by-step explanation:
Answer:
3.2 in fraction form is 3 1/5
if the . is a multiplication sign then it is 6
Answer:
The water temperature that produces the maximum number of salmon swimming upstream is approximately 12.305 degrees Celsius.
Step-by-step explanation:
Let , for . represents the temperature of the water, measured in degrees Celsius, and is the number of salmon swimming upstream to spawn, dimensionless.
We compute the first and second derivatives of the function:
(Eq. 1)
(Eq. 2)
Then we equalize (Eq. 1) to zero and solve for :
And all roots are found by Quadratic Formula:
,
Only the first root is inside the given interval of the function. Hence, the correct answer is:
Now we evaluate the second derivative at given result. That is:
According to the Second Derivative Test, a negative value means that critical value leads to a maximum. In consequence, the water temperature that produces the maximum number of salmon swimming upstream is approximately 12.305 degrees Celsius.