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
Answer:
48
Step-by-step explanation:
66*2=132
180-132=48
Answer:
30 minutes
Step-by-step explanation:
First you can break down the percent and the time into a fraction
You can divide it by 2
so 2%/1 (2% in 1 minute)
Then you find the amount of time it would take to paint the whole bookcase
2 * 100 = 50
So time to paint the whole bookcase would be 50
50 - 20 = 30
It will take him 16 hours because 25 is 1/4 of 100% so 4 times 4 is 16. So 16 is your answer :)
So there’s a flat fee of 2 and that’s like a standalone thing so our equation would be
2 + 1.50m
Assuming m = 9, it would be 2 + 13.50
And the two answers are-
A) $15.50
B) 2 + 1.50m
