Answer:
a). 59.049°C
b). 2.1179 seconds
Step-by-step explanation:
Expression representing the final temperature after decrease in temperature of the metal from 100°C to T°C is,
T = 
where x = duration of cooling
a). Temperature when x = 5 seconds
T = 100(0.9)⁵
= 59.049
≈ 59.049°C
b). If the temperature of the metal decreases from 100°C to 80°C
Which means for T = 80°C we have to calculate the duration of cooling 'x' seconds
80 = 
0.8 = 
By taking log on both the sides
log(0.8) =log[
]
-0.09691 = x[log(0.9)]
-0.09691 = -0.045757x
x = 
x = 2.1179
x ≈ 2.1179 seconds
Use PEMDAS:
P Parentheses first
E Exponents (ie Powers and Square Roots, etc.)
MD Multiplication and Division (left-to-right)
AS Addition and Subtraction (left-to-right)
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Answer:
Option D.
Step-by-step explanation:
The total stock of currency and other liquid instruments circulating in the economy of a country as of a particular time is known as money supply.
If the reserve requirements of banks is least then banks are able to loan more money, that will increases the overall supply of money in the economy.
In 100% reserve banking system, 100% amount of each depositor's funds would be required to keep by bank for immediate withdrawal on demand.
100% reserve banking system is also known as Full-reserve banking system.
It means, if a customer deposits $100 of currency into a bank with 100% reserve banking system, then the money supply remains the same.
Therefore, the correct option is D.
B)257.1
Explanation: Area of a square : length x width
Area of square = 12x12= 144
Area of a circle: pie(radius)^2
diameter:12
radius:12/2=6
Area of a circle: pie(6)^2=113.1
ADD BOTH AREAS
Area of the figure =144+113.1
=257.1
Answer:
Step-by-step explanation:
2+3=6
135/6=22.5
22.5x2=45