Answer:
ΔT = ΔT0 e^-K T
As I understand Newton's Law of Cooling
ΔT at any time is the difference between the temperature and the surroundings
Originally ΔT0 = 95 - 22 difference between 95 and room temperature
65 - 22 = 33 = 73 e^-KT where t is time to cool to 65 deg
ln (33/73) = -KT K = .794 / 5 = .159 where 5 is time to cool to 65 deg
40 - 22 = 73 e^-.159 T where t is time to cool to 40 deg
18 = 73 e^-.159 T
ln (18 / 73) = -.159 T
T = 8.8 min
It would take 8.8 min for the object to cool to 40 deg C
Suppose the object cooled from 95 to 90 deg, then
ln 68 / 73 = -.159 T and T = .45 min
Answer:
10
Step-by-step explanation:
I assume it's a rectangle, therefore:
P = 50
a = 15 ft
b = ?
P = 2a + 2b
50 = 2 * 15 + 2b
50 = 30 + 2b
2b = 50 - 30
2b = 20
b = 10
Answer:
B and C. can you select more than one?
9514 1404 393
Answer:
y = -1/2x + 3
Step-by-step explanation:
It can work to start with the 2-point form of the equation for a line.
y = (y2 -y1)/(x2 -x1)(x -x1) +y1
y = (1 -5)/(4 -(-4))(x -(-4)) +5 . . . . . fill in point values
y = -4/8(x +4) +5 . . . . . . . . simplify a bit
y = -1/2x -2 +5 . . . . . .eliminate parentheses
y = -1/2x +3 . . . . collect terms
Answer:
19
Step-by-step explanation:
y = 6x - 11 If x = 5
y = (6*5) - 11
y = 30 - 11
y = 19
