Answer:
212.9 years
Step-by-step explanation:
Given that the half-life of cesium-137 is 30 years. Suppose we have a 170 mg sample
P0 = 175
P(30) = 87.5
So we can write equation as
b) After 60 years t = 30
In 30 years it becomes half and hence in 60 years it would become 1/4
i.e. 
mg
c) If P(t) =1, let us find t
212.9
Except (D)
because it's 25N not 0.25N
Answer:
0.0003W/cm°C
Step-by-step explanation:
The question is not properly written. Here is the correct question.
The batting wang xiu ying uses to fill quilts has a thermal conductivity rate of 0.03 watts (W) per meter(m) per degree celsius. what is the batting thermal conductivity when w/cm•c
Given the thermal conductivity in W/m°C to be 0.03W/m°C
We are to rewrite the value in W/cm°C
The difference is the unit. The only thing we need to do is to simply convert the unit (metres) in W/m°C to centimeters (cm)
Since 100cm = 1m, 0.03W/m°C can be expressed as shown below;
= 0.03W/m°C
= 0.03 × W/1m×°C
Note that 1m = 100cm, substituting this conversion into the expression, it will become;
= 0.03 × W/100cm × °C
= 0.03/100 × W/cm°C
= 0.0003W/cm°C
Hence the battling thermal conductivity in W/cm°C is 0.0003W/cm°C
Let the speed of the current be y and the speed of Micah's sailing speed be x. Then 4.48/(x + y) = 0.32
4.48/(x - y) = 0.56
0.32x + 0.32y = 4.48 . . . (1)
0.56x - 0.56y = 4.48 . . . (2)
(1) x 7 => 2.24x + 2.24y = 31.36 . . . (3)
(2) x 4 => 2.24x - 2.24y = 17.92 . . . (4)
(3) - (4) => 4.48y = 13.44
y = 3
From (1), 0.32x + 0.32(3) = 4.48
0.32x = 4.48 - 0.96 = 3.52
x = 3.52/0.32 = 11
Therefore, the speed of the current is 3 miles per hour.
Answer:
Coldslaw
Step-by-step explanation:
