Answer:
10n+(10 x 15)
or
(10 x n)+150
either way it would be 270
square has 4 equal sides
so A = 144 = 12^2
A = L x W
= W. W
= W^2
12^2 = W^2
so W = 12
answer: one side of the square = 12
Answer: 693 years
Step-by-step explanation:
Expression for rate law for first order kinetics is given by:

k = rate constant
t = time taken for decomposition = 1
= Initial amount of the reactant
= amount of the reactant left =



for half life : 

Putting in the values , we get


Thus half life of this isotope, to the nearest year is 693.
Answer:
86
Step-by-step explanation:
In this question, we are asked to calculate the average mean score for a group of students split into two different emerging groups.
We calculate the total score for each of the groups. This is done by multiplying the average score by the number of students.
Total score of section A is 15 * 80 = 1,200
For section B, total score is 20 * 90 = 1,800
Overall score is thus 1200 + 1800 = 3000
We add the scores together and divide by the total number of students in both sections
Average score is thus 3000/35 = 85.71 which is approximately 86
21/186
Answer: 7/62
Hope this helps!!!!!!!