The rate a which the surface area, S, decreases is

The surface area is
S = 4πr²
where r = the radius at time t.
Therefore

When r = 3 cm, obtain
![\frac{dr}{dt}]_{r=3} = - \frac{1}{3} \, cm/s](https://tex.z-dn.net/?f=%20%5Cfrac%7Bdr%7D%7Bdt%7D%5D_%7Br%3D3%7D%20%3D%20-%20%5Cfrac%7B1%7D%7B3%7D%20%5C%2C%20cm%2Fs%20%20)
Answer: -1/3 cm/s (or -0.333 cm/s)
Answer: 0.6666... (never ending digit)
Step-by-step explanation:
2/3 divide the numerator, '2' by the denominator '3'
6x3= 18 + g =18g (Hope this helped!)
Answer: 
Step-by-step explanation:
Given: A bag contains 2 black balls, 4 yellow balls and 4 white balls.
Event A is defined as drawing a white ball on the first draw.
Event B is defined as drawing a black ball on the second draw.
P(B|A) is expressed as the conditional probability of occurring B given that A.
i.e. it is the probability of happening B where A is already happended.
If a white ball is drawn at first, then the number of black ball(4) remains unchanged but the total number of balls (10) will become 9.

Then, 