Answer: -1
Step-by-step explanation:
f(t) = -2t + 3
f(-2) = -2 x -2 + 3 [ substituting the value]
f(-2) = -4 + 3
f(-2) = -1
Answer:
Option A - 
Step-by-step explanation:
We have given the expression 
We have to find the value of the expression ?
Solution :
Step 1 - Write the expression

Step 2 - Applying symbol rule i.e. multiplication of positive into negative is always negative, 

Step 3 - Solve

Therefore, The value of the expression is 
So, Option A is correct.
Its A or C because Angle AEC has to be bigger then 90 degrees
Answer:
9r
Step-by-step explanation:
1.5r - 3r + 10.5r
10.5r + 1.5r = 12r
12r - 3r = 9r
Final Answer = 9r
The percentage of the radioactive isotope left is 25.0000%.
<h3>What is the half life?</h3>
The half life of a radioactive isotope is the time that will elapse before only half of the number of original isotopes will remain.
Now;
We are told that;
Half life (t1/2) = 55 days
Time taken (t) = 115 days
Ratio of isotope remaining = N/No
Thus;
N/No = (1/2)^t/t1/2
N/No = (1/2)^115/55
N/No = (1/2)^2
N/No =1/4
Hence, the percentage = 1/4 * 100/1 = 25.0000%
Learn more about half life of an isotope:brainly.com/question/16387602
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