<h3>
Answer:</h3>
- running speed: 8 mph
- walking speed: 2 mph
<h3>
Step-by-step explanation:</h3>
Let w represent Lizette's walking speed. Then her running speed is w+6. The relationship between speed, time, and distance is ...
distance = speed × time
Lizette ran for 1.5 hours, then walked for 3 hours. Her total distance is ...
(w+6)·1.5 + w·3 = 18
4.5w + 9 = 18 . . . . . simplify
4.5w = 9 . . . . . . . . . subtract 9
w = 2 . . . . . . . . . . . .divide by 4.5
Lizette's walking speed is 2 mph; her running speed is 8 mph.
Answer:
-816.8 ft²/min
Step-by-step explanation:
The rate of change of area is the product of the rate of change of radius and the circumference of the circle. At the time of interest, ...
dA/dt = C·dr/dt = 2πr·dr/dt
dA/dt = 2π·(26 ft)(-5 ft/min)
dA/dt = -260π ft²/min ≈ -816.8 ft²/min
<span>Answer:
MgF2 ====⇒ Mg+2 + 2F-
Ksp = [Mg+2][F-]^2
Let S = molar solubility of MgF2
[Mg+2] = S ; [F-] = 2s
Since the [F-] is initially 0.40 M, then [F-] = 0.40 + 2S
6.4 x 10^-9 = (S) (0.40 + 2S)^2 ; one can neglect the 2S in the 0.40 + 2S expression since it is very, very small compared to the 0.40 already present.
6.4 x 10^-9 = S(0.40)^2
S = 4.0 x 10^-8
Molar solubility = 4.0 x 10^-8</span>
23 and 2 tens is 23 and 20 which equals 53
53
Answer:
k=m+4
Step-by-step explanation: