Answer:
-1/root2
Step-by-step explanation:
7pi/4 radians is the same as -pi/4 radians
sin(-pi/4) is -sin(pi/4) = -1/root2
Answer:
B. 8
Step-by-step explanation:
cos37° = 4/5 = x/10
=> 4(10) = 5x
=> x = 40/5
=> x = 8
The correct option is B.
Answer:
PS = 10 
Step-by-step explanation:
Answer:
The new TV screen is 12.1 centimeters wide.
Step-by-step explanation:
Find 10% of 11:
0.10 x 11 = 1.1
Add 1.1 to the original size.
11 + 1.1 = 12.1
hope this helps
The question is incomplete, here is the complete question:
The half-life of a certain radioactive substance is 46 days. There are 12.6 g present initially.
When will there be less than 1 g remaining?
<u>Answer:</u> The time required for a radioactive substance to remain less than 1 gram is 168.27 days.
<u>Step-by-step explanation:</u>
All radioactive decay processes follow first order reaction.
To calculate the rate constant by given half life of the reaction, we use the equation:
where,
= half life period of the reaction = 46 days
k = rate constant = ?
Putting values in above equation, we get:
The formula used to calculate the time period for a first order reaction follows:
where,
k = rate constant =
t = time period = ? days
a = initial concentration of the reactant = 12.6 g
a - x = concentration of reactant left after time 't' = 1 g
Putting values in above equation, we get:
Hence, the time required for a radioactive substance to remain less than 1 gram is 168.27 days.