A stone is dropped into a lake, creating a circular ripple that travels outward at a speed of 60 cm/s. Required:
a. Express the radius r (in cm) of this circle as a function of time t (in seconds).
r(t) = cm

b. If A is the area of this circle as a function of the radius.
Find A ∘ r.
(A ∘ r)(t) =

answer:

a=9

step-by-step explanation: lmk if you need a explanation

c

step-by-step explanation:

a28=58

step-by-step explanation:

a1=a1+(n-1)d

a28= 4+ (28-1)2

a28=4+(27)(2)

a28=4+54

a28=58

answer: c.  

step-by-step explanation:

mixtures containing substances that get attracted to magnet can be separated using a magnet. we can separate iron from a mixture of sand and iron, as only iron attracts to the magnet.