I think it's the first 7.
I hope this helps :-)
Answer:
7.5 ft³/min
Step-by-step explanation:
Let x be the depth below the surface of the water. The height, h of the water is thus h = 10 - x.
Now, the volume of water V = Ah where A = area of isosceles base of trough = 1/2bh' where b = base of triangle = 4 ft and h' = height of triangle = 1 ft. So, A = 1/2 × 4 ft × 1 ft = 2 ft²
So, V = Ah = 2h = 2(10 - x)
The rate of change of volume is thus
dV/dt = d[2(10 - x)]/dt = -2dx/dt
Since dV/dt = 15 ft³/min,
dx/dt = -(dV/dt)/2 = -15 ft³/min ÷ 2 = -7.5 ft³/min
Since the height of the water is h = 10 - x, the rate at which the water level is rising is dh/dt = d[10 - x]/dt
= -dx/dt
= -(-7.5 ft³/min)
= 7.5 ft³/min
And the height at this point when x = 8 inches = 8 in × 1 ft/12 in = 0.67 ft is h = (10 - 0.67) ft = 9.33 ft
3. 180 - (53+68) = 59
The answer is B. 59°
4.
Part A: The measure of a is 70°.
Explanation: The angle sum in any triangle is 180°. 70 + 40 is 110. To find the final angle, subtract 110 from 180. 180 - 110 = 70
Part B: The length of x is 5m.
Explanation. The triangle is an isosceles triangle. We know this because the two angles on the base are equal. Since this is an isosceles triangle, the two longer sides are the same length. Therefore: x = 5 m.
8*a=32
32:8=a
4=a
4+26=b
30=b
Answer:
C=24π
Step-by-step explanation:
C=2πr
C=2π12
C=24π
≈75.39