Answer:
She spent 25 minutes studying last week
Step-by-step explanation:
L = last week
120 = 4L + 20
Subtract 20 from either side
100 = 4L
Divde either side by 4
25 = L
Answer:
138
Step-by-step explanation:
p(x) = 3x^4 + 2x^3 − 4x^2 + 21
Let x = 2
p(2) = 3*(2)^4 + 2*(2)^3 − 4*(2)^2 + 21
= 3*16+2*8-4*4+21
=48+16-16+21
= 69
This is per girl
There are 2 girls
2 * 69
138
Assuming R and H:
So volume is pir^2 * H = 1500 and H = 1500/(pir^2) while surface area is A= 2pir*H + 2pir^2
A = 2pir(r+h)= 2piR^2 + 2pir*1500/(pir^2)= 2piR^2 + 3000/r
For A to take minimum, get the derivative 4pir - 3000/R^2 and let it be 0
4pir^3 - 3000 = 0
r = cbrt(3000/(4pi)) ≈ 6.20
h = 1500/(pi(6.20)^2) ≈ 12.42
