Answer:
Domain: 
Range: 
Step-by-step explanation:
Given

Required
Determine the domain and the range
Solving for domain:
From the question, we understand that t represent years.
Because years can't be negative;
Then, we can conclude that the domain, t is:

Solving for Range:
We solved domain to be 
This implies that the minimum value of t is
and the maximum is infinity
Substitute 0 for t in 



Hence;
The range is 
Answer:
Provided in the picture below.
Step-by-step explanation:
Provided in the picture below.
Answer:
0.0359
Step-by-step explanation:
Data provided:
mean values of three independent times are 15, 30, and 20 minutes
the standard deviations are 2, 1, and 1.6 minutes
Now,
New Mean = 15 + 30 + 25 = 65
Variance = ( standard deviation )²
or
Variance = 2² + 1² + 1.6² = 7.56
therefore,
Standard deviation = √variance
or
Standard deviation = 2.75
Thus,
Z-value = 
or
Z-value = - 1.81
from the Z-table
the Probability of Z ≤ -1.81 = 0.0359
∠ROT=160°
∠SOT=100°
Now ∠SOR= ∠ROT - ∠SOT
∠ SOR = 160°-100°
∠ SOR =60°
It is given that measure of angle ROQ to equals the measure of angle QOS equals the measure of angle POT.
∠SOQ + ∠QOR = 60°
But ∠SOQ = ∠QOR
2∠SOQ=60°
∠SOQ=60°÷2
∠SOQ =30°
Also ∠POT=∠SOQ=∠ROQ=30°
Answer:
The answer is 15%.
Step-by-step explanation:
The probability that:
- Both treatments are successful:
80% x 90% = 72%
- The first method is a success, but the second one is not:
80% x (1 - 90%) = 8%
- The first method is not successful, but the second one is:
(1 - 80%) x 25% = 5%
- Both treatments are unsuccessful:
1 - (72% + 8% + 5%) = 15%