Let x be the number of racing bikes, and let y be the number of mountain bikes.
1) 140x + 110y = 26150
2) 180x + 120y = 31800
Solve for one of the variables and plug that in to the other equation:
From equation 1: 140x = 26150 - 110y
x = (26150-110y)/140
Plug this into equation 2:
180((26150-110y)/140) = 31800
Solve for y, and find that y = 85 (the number of mountain bikes).
Plug that y into either equation to find x:
140x + 110(85) = 26150
x = 120 (the number of racing bikes).
So the answer is: 120 racing bikes and 85 mountain bikes.
Answer: a - 4.512 hours
b - 1.94 hours
Step-by-step explanation:
Given,
a) A(t) = 10 (0.7)^t
To determine when 2mg is left in the body
We would have,
A(t) = 2, therefore
2 = 10(0.7)^t
0.7^t =2÷10
0.7^t = 0.2
Take the log of both sides,
Log (0.7)^t = log 0.2
t log 0.7 = log 0.2
t = log 0.2/ 0.7
t = 4.512 hours
Thus it will take 4.512 hours for 2mg to be left in the body.
b) Half life
Let A(t) = 1/2 A(0)
Thus,
1/2 A(0) = A(0)0.7^t
Divide both sides by A(0)
1/2 = 0.7^t
0.7^t = 0.5
Take log of both sides
Log 0.7^t = log 0.5
t log 0.7 = log 0.5
t = log 0.5/log 0.7
t = 1.94 hours
Therefore, the half life of the drug is 1.94 hours
Answer:

Step-by-step explanation:
Total Surface Area of Cylinder = 
Given from the question, r = 7 cm and h = 15cm
Lets Substitute r and h into the formula to find the Total Surface Area of the cylinder.
Total Surface Area of Cylinder = 
Answer: D
Step-by-step explanation: I believe it's D because there's a STRONG, POSITIVE RELATIONSHIP so they're both increasing, but there's no correlation