Answer:

Step-by-step explanation:
Given Data,
Q=23000 J
c=4.184 J/g °c
Δt= 68 °c
m=?
By using this equation,
Q=mcΔt

Answer:
x = 25
Step-by-step explanation:
.20x + .68(120 - x) = .54(120) (Distribute .68 to 120 and -x)
.20x + 81.6 - .68x = .54(120) (multiply .54 and 120)
.20x + 81.6 - .68x = 69.6 ( add .20x and -.68x)
-.48x + 81.6 = 69.6 ( subtract 81.6 on each side)
-.48x = -12 (divide -12 by -.48)
x = 25
Its 12. Part a was 2 part b was 3
6×2=12
4×3=12
Answer:
Point estimate for the population variance = 3.92 *
.
Step-by-step explanation:
We are given that a sample of 5 strings of thread is randomly selected and the following thicknesses are measured in millimeters ;
X X -
1.13 1.13 - 1.188 = -0.058 3.364 * 
1.15 1.15 - 1.188 = -0.038 1.444 *
1.15 1.15 - 1.188 = -0.038 1.444 * 
1.24 1.24 - 1.188 = 0.052 2.704 * 
1.27 1.27 - 1.188 = 0.082 <u> 6.724 * </u>
<u> </u>
<u>= 0.01568 </u>
Firstly, Mean of above data,
=
=
= 1.188
Point estimate of Population Variance = Sample variance
=
=
= 3.92 *
.
Therefore, point estimate for the population variance = 3.92 *
.